do you want 29mm or 24mm? estes D's E's and some F's like the F21 are all 24mm, but if you want to get some junk in the trunk, ie G power, once you've gotten bored with the D's E's and F's. then 29mm would give you a huge variety. not only that, but a lot of really kick butt motors are 29mm, while there are SOME sweet 24mm motors, its a lot better to start with a 29mm mount and throw an adapter in to run it on. just something to think about.
for under 40 bucks, the onyx is a really nice kit, but if you want something a little more sleek looking, i'd go with the loc forte.