Do you know there's now a ProPlus 3 out? If not, take a long, hard look and what you get for the price difference, and make your decision accordingly.
I like air integration in computers that incorporate the info. into the log for download to computer later, which saves me the bother of writing down entry & exit pressures, and calculates a SAC automatically.
I think a ProPlus 2.1 or 3 would do fine for most any diving you care to do aside from tech. diving, and really, by the time you're ready to push into that, at the rate technology advances, isn't it fairly likely you're going to want a new computer then anyway?
If not, and you want one that can grow into tech., cool, check out the Shearwater Petrel.
Richard.