This system is FAR easier to use than previous editions, while losing none of the complexity. Ability scores all use the same bonus table, skill checks are based on abilities, and just about everything in the game boils down to a basic skill or ability check with modifiers. Trust me, it's much easier to use. 3 basic saving throws, each based on an ability score. The races are much more clarified and notably different, class groups are gone, replaced by a large number of classes that just about stand on their own.
Spells are far easier to categorize, and spell use is a little more widespread.
All told, it's well worth it to upgrade. Here's a really simple topic that covers something I've been thinking about. Ok, so we've all played through Half-Life, Opposing Force, and probably They Hunger. Go on, tell me . Quite, although I could stand to see it once, I suppose.