What kind of pattern do you want to fly? SPA and CPA have gained a lot of popularity lately, so several manufacturers are making ARFs and kits for that. The difference between the two is that SPA requires standard mufflers and fixed gear, while CPA allows pipes and retracts. And of course, if those advantages are allowed, they are pretty much required to be competitive. The Kaos is easily the most popular plane for SPA, and the Dirty Birdy is probably the most common for CPA. Neither are particularly expensive, although I've seen guys sink a few dollars into their CPA planes with the really hot engines and good retracts trying to get the last little bit of performance out of them. But if you're talking about F3A which is the current high performance pattern competition, that gets you into fairly large planes with fairly expensive power systems and electronics so it's a whole different level of commitment. Of course, if you're just talking about building your skills by learning some of the sequences, it's not necessary to have a dedicated plane for it. An Ugly Stick will work fine, as will any number of other sport planes that have fairly neutral handling.