I just mentally seem to like the idea of the soft handled screwdrivers. Just like I like the comfort grip for ratchets. I guess I'll never know till I try. Maybe I'll get a set of hard handle torx and my phillips and slotted screwdrivers in soft.
I have the Instinct Soft, and the Williams Hard Handles. I'm always grabbing for the SO's, and anybody that says they don't last, are a magnet for dirt and grime, fall apart etc. Has never owned a set and put them to harsh work. Expensive but the best in my opinion.
The Williams are excellent (especially for the money). The actual 'Business end' are indistinguishable from the SO's both in appearance and durability. I much prefer the Instinct handles though, but I wouldn't have bought them just for that if not for the deal I worked out with a SO driver.
Either way, they're both good buys depending on how much you use them.