I know a lot of people at my school don't like the HP49. I've never used a 49 so I don't really know. The TI-89 is pretty nice, I tried using somebody's one time and the interface is a lot different from their previous calculators. Basically, I use my TI-85 for most simple stuff, and I use my 48G whenever I want to do anything symbolic, or simultaneous equations, etc.