Yeah my first two thoughts were it looks like a good setup, but then it looks a bit small. Remember the rule where the diameter is supposed to be twice the size of the mantis (doesn't look like that might be the case) and the height thrice the mantids length. I've always thought that rule was a little bit...pushing it. I guess why thats good to keep in mind those are like the absolute minimums. I like them to have at least 3 times their length for diameter (or length and width for rectangular prisms) as a minimum. (Remember, all the rules are really rule of thumbs!)
In my experience this is because they tend to get eye rub in smaller enclosures. (Like every time I've put one in too small an enclosure for a molt or longer they come out with a little eye rub. I've since stuck to larger setups, and taking them out of Tupperware containers sooner.