I guess everyone has different needs and goals. One of mine is a need for IFR capability; my aircraft is currently IFR capable & authorized, and I'm trying to improve it....EFIS seems the way to go. So, the miniature Becker-style radios are not an option (no Nav radio of that style I've seen). The SL-30 type is sweet, can hook into EFIS, and both can be controlled by my stick grip, which would be huge.
I'd pay attention to brightness, backlighting, etc. as someone else suggested.
Good luck.