Anyone keep dead leaf, shield, African twig and budwing mantids?

There's a guy near me that sell these as adults or hatchlings for $5-$10 a piece, is that a good price? I guess he's the mantid enthusiast in my area, but I was wondering what rank these species are in the world of mantids. I'm checking to see if they're as special or rare as he claims I have never owned any mantids nor have I read up on any, so I am a bit in the dark with these, but I am interested in them because they are quite beautiful and would not mind adding them to my collection of inverts.

Any comments welcome and thanks for looking.