IMHO the most important thing in glide computers are display and user interface. Latter on is all about software. I like the idea of getting best possible sensor suite/variometer money can buy, and then choosing the software and display of your preferences to run moving map, task optimization, final glide calculation etc. Display technologies evolve (admittedly slowly) and new features are added to gliding softwares all the time. I would not invest several thousands to computer with a hope that manufacturer will keep the software up-to-date for decades.