I thought this was going to be one of securesparks "what shall I buy?" posts ! Those Stanley screwdrivers are OK until the ratchet fails and the bits get chewed up, they're a bit soft.
Yeah, but in honesty the OP sounds like (s)he is just starting out with a bit of DIY tinkering so for that purpose they will be ok'ish for a first time purchase. (Personally wouldn't give em house room, but that's a totally different kettle of fish)
I've got battery drill drivers too, a bigger and smaller makita as well as some older nicad ones. The hours my impact driver has saved me on various projects. It really is a great bit of kit.
@OM2 - the makita is an impact driver, so it will turn like a normal drill driver, but if the screw is stuck or tight, it will start to turn less and hammer more. You tend to wear out the bits a bit quicker, but you rarely smash the screw head, because you can get all your weight behind the driver and let the mechanism do the rest. Perfect for things like frame fixers, but also any screw really. If you are having one drill driver for many jobs, then what you bought is better, because you can drill holes too.
for general screwing drilling driving around the house get a decent hammer drill
only get an impact if you have loads off heavy screwing off say 60mm plus screws and dont need to drill many holes and non in hard walls
do not use an impact on any delicate work or small screws off say less than 30mm
yes you can use it with great skill but its the wrong tool