Wow, those are actually pretty... Kind of remind me of the silver eastern morph.

I'm generally against cross breeding in pretty much any sort of reptile/amphibian. It's really common in pacman frogs, where a cranwelli x ornata gives you a much more desirable morph. It's so common that people talk about it almost like it's a species (Fantasy frog) This got people into thinking that whatever species of horned frog you mixed would end up giving you a good cross, and they ended up with a crossbreed called a 'green apple'. They are beautiful, but they almost all have severe spinal problems, and a lot of them don't even reach adulthood. The ones that do are usually sickly and terrible eaters. It really bothers me that people still try to create them knowing this. I'd hate to see something like that happen with garters.
Besides, no cross is as cool looking as the morphs you can get from just one species.