I use PIC 18 series
They're larger, but they're nice... And not to mention free
The MPLAB IDE program is pretty nice. It doesn't limit you very much. If you get an inline debugger (MPLAB ICD 2), it allows you to run your robot and do any tests you want with your microcontroller. You can input stuff and figure out what may be wrong with your robot. I'm not sure if you already use MPLAB and such.
With MPLAB though, you can get C18 compiler, which is what I use. So you can program in C peticualrly for the p18xxx set of chips.
I actually have a development board that I can burn my programs onto the chip. I doubt you want to spend $150 though. Let me get back, I have to go take a quick test. Stupid ACT studying o_o Gotta get into CMU though