diff --git a/README.md b/README.md
index b027ae47..4bd81595 100644
--- a/README.md
+++ b/README.md
@@ -13,7 +13,7 @@ This repository is based on [@zeerorg](https://github.com/zeerorg/)'s [zeerorg/k
 
 - [docker](https://docs.docker.com/install/)
 
-## Install
+## Get
 
 You have several options there:
 
@@ -21,7 +21,7 @@ You have several options there:
   - wget: `wget -q -O - https://raw.githubusercontent.com/rancher/k3d/master/install.sh | bash`
   - curl: `curl -s https://raw.githubusercontent.com/rancher/k3d/master/install.sh | bash`
 - Grab a release from the [release tab](https://github.com/rancher/k3d/releases) and install it yourself.
-- Via go: `go install github.com/rancher/k3d`
+- Via go: `go install github.com/rancher/k3d` (**Note**: this will give you unreleased/bleeding-edge changes)
 
 or...
 
@@ -32,7 +32,7 @@ or...
    - 'make install-tools' to make sure required go packages are installed
 3. Inside the repo run
    - `make build` to build for your current system
-   - `go install` to install it to your `GOPATH`
+   - `go install` to install it to your `GOPATH` (**Note**: this will give you unreleased/bleeding-edge changes)
    - `make build-cross` to build for all systems
 
 ## Usage
diff --git a/cli/commands.go b/cli/commands.go
index 1ffa7769..956c26d1 100644
--- a/cli/commands.go
+++ b/cli/commands.go
@@ -23,6 +23,8 @@ import (
 	"github.com/urfave/cli"
 )
 
+const defaultRegistry = "docker.io"
+
 // CheckTools checks if the docker API server is responding
 func CheckTools(c *cli.Context) error {
 	log.Print("Checking docker...")
@@ -43,6 +45,28 @@ func CheckTools(c *cli.Context) error {
 // CreateCluster creates a new single-node cluster container and initializes the cluster directory
 func CreateCluster(c *cli.Context) error {
 
+	if err := CheckClusterName(c.String("name")); err != nil {
+		return err
+	}
+
+	// define image
+	image := c.String("image")
+	if c.IsSet("version") {
+		// TODO: --version to be deprecated
+		log.Println("[WARNING] The `--version` flag will be deprecated soon, please use `--image rancher/k3s:<version>` instead")
+		if c.IsSet("image") {
+			// version specified, custom image = error (to push deprecation of version flag)
+			log.Fatalln("[ERROR] Please use `--image <image>:<version>` instead of --image and --version")
+		} else {
+			// version specified, default image = ok (until deprecation of version flag)
+			image = fmt.Sprintf("%s:%s", strings.Split(image, ":")[0], c.String("version"))
+		}
+	}
+	if len(strings.Split(image, "/")) <= 2 {
+		// fallback to default registry
+		image = fmt.Sprintf("%s/%s", defaultRegistry, image)
+	}
+
 	// create cluster network
 	networkID, err := createClusterNetwork(c.String("name"))
 	if err != nil {
@@ -81,7 +105,7 @@ func CreateCluster(c *cli.Context) error {
 	log.Printf("Creating cluster [%s]", c.String("name"))
 	dockerID, err := createServer(
 		c.GlobalBool("verbose"),
-		fmt.Sprintf("docker.io/rancher/k3s:%s", c.String("version")),
+		image,
 		c.String("port"),
 		k3sServerArgs,
 		env,
@@ -144,7 +168,7 @@ func CreateCluster(c *cli.Context) error {
 		for i := 0; i < c.Int("workers"); i++ {
 			workerID, err := createWorker(
 				c.GlobalBool("verbose"),
-				fmt.Sprintf("docker.io/rancher/k3s:%s", c.String("version")),
+				image,
 				k3sWorkerArgs,
 				env,
 				c.String("name"),
diff --git a/cli/util.go b/cli/util.go
index 66d0ba2b..1688c57b 100644
--- a/cli/util.go
+++ b/cli/util.go
@@ -1,6 +1,7 @@
 package run
 
 import (
+	"fmt"
 	"math/rand"
 	"strings"
 	"time"
@@ -36,3 +37,35 @@ func GenerateRandomString(n int) string {
 
 	return sb.String()
 }
+
+/*** Cluster Name Validation ***/
+const clusterNameMaxSize int = 35
+
+// CheckClusterName ensures that a cluster name is also a valid host name according to RFC 1123.
+// We further restrict the length of the cluster name to maximum 'clusterNameMaxSize'
+// so that we can construct the host names based on the cluster name, and still stay
+// within the 64 characters limit.
+func CheckClusterName(name string) error {
+	if len(name) > clusterNameMaxSize {
+		return fmt.Errorf("[ERROR] Cluster name is too long")
+	}
+
+	if name[0] == '-' || name[len(name)-1] == '-' {
+		return fmt.Errorf("[ERROR] Cluster name can not start or end with - (dash)")
+	}
+
+	for _, c := range name {
+		switch {
+		case '0' <= c && c <= '9':
+		case 'a' <= c && c <= 'z':
+		case 'A' <= c && c <= 'Z':
+		case c == '-':
+			break
+		default:
+			return fmt.Errorf("[ERROR] Cluster name contains characters other than 'Aa-Zz', '0-9' or '-'")
+
+		}
+	}
+
+	return nil
+}
diff --git a/main.go b/main.go
index aa3e40a9..94d70519 100644
--- a/main.go
+++ b/main.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"fmt"
 	"log"
 	"os"
 
@@ -9,6 +10,10 @@ import (
 	"github.com/urfave/cli"
 )
 
+// defaultK3sImage specifies the default image being used for server and workers
+const defaultK3sImage = "docker.io/rancher/k3s"
+const defaultK3sClusterName string = "k3s-default"
+
 // main represents the CLI application
 func main() {
 
@@ -48,7 +53,7 @@ func main() {
 			Flags: []cli.Flag{
 				cli.StringFlag{
 					Name:  "name, n",
-					Value: "k3s_default",
+					Value: defaultK3sClusterName,
 					Usage: "Set a name for the cluster",
 				},
 				cli.StringFlag{
@@ -60,8 +65,8 @@ func main() {
 					Usage: "publish k3s node ports to the host (Docker notation: `ip:public:private/proto`, use multiple options to expose more ports)",
 				},
 				cli.StringFlag{
+					// TODO: to be deprecated
 					Name:  "version",
-					Value: version.GetK3sVersion(),
 					Usage: "Choose the k3s image version",
 				},
 				cli.IntFlag{
@@ -78,6 +83,11 @@ func main() {
 					Name:  "wait, w",
 					Usage: "Wait for the cluster to come up before returning",
 				},
+				cli.StringFlag{
+					Name:  "image, i",
+					Usage: "Specify a k3s image (Format: <repo>/<image>:<tag>)",
+					Value: fmt.Sprintf("%s:%s", defaultK3sImage, version.GetK3sVersion()),
+				},
 				cli.StringSliceFlag{
 					Name:  "server-arg, x",
 					Usage: "Pass an additional argument to k3s server (new flag per argument)",
@@ -102,7 +112,7 @@ func main() {
 			Flags: []cli.Flag{
 				cli.StringFlag{
 					Name:  "name, n",
-					Value: "k3s_default",
+					Value: defaultK3sClusterName,
 					Usage: "name of the cluster",
 				},
 				cli.BoolFlag{
@@ -119,7 +129,7 @@ func main() {
 			Flags: []cli.Flag{
 				cli.StringFlag{
 					Name:  "name, n",
-					Value: "k3s_default",
+					Value: defaultK3sClusterName,
 					Usage: "Name of the cluster",
 				},
 				cli.BoolFlag{
@@ -136,7 +146,7 @@ func main() {
 			Flags: []cli.Flag{
 				cli.StringFlag{
 					Name:  "name, n",
-					Value: "k3s_default",
+					Value: defaultK3sClusterName,
 					Usage: "Name of the cluster",
 				},
 				cli.BoolFlag{
@@ -166,7 +176,7 @@ func main() {
 			Flags: []cli.Flag{
 				cli.StringFlag{
 					Name:  "name, n",
-					Value: "k3s_default",
+					Value: defaultK3sClusterName,
 					Usage: "Name of the cluster",
 				},
 				cli.BoolFlag{