The multi bit power drivers have been out for years now and I don't see to many people using them and many don't even know what a power driver is. I have to admit I don't use mine everyday but I do use my Klein 10 in 1 all day everyday its just so much easier to grab one screwdriver and go. The problem is that they are bulky and the 6 in 1 is just huge, this isn't a problem all the time but sometimes it doesn't fit to get the screw out. I really like the 5 in 1 its a little bulky but not to bad I wish it had a 5/16 nutdriver on it in then it would be almost perfect. In order to get the 5/16 nutdriver you have to buy the 6 in 1 which is just humongous and just dosen't look right. I'm no engineer but if Klein can make a 10 in 1 in a small diameter with a 5/16 nutdriver they should be able to make a small diameter 5/16 power driver. I might just take the handle off my 10 in 1 and stick it in my drill and use it as a power driver but I know it will just strip out the nutdriver because the metal is so thin The 6 in 1 is so large that the 5 in 1 fits inside it with room to spare..lol (pics below)