I've just gone down this route to access the kit for our service engineers. 1 thing to be wary of. Not all things are equal. There are different grades of chuck, battery and switch. Which is why some outlets can offer very good prices of what looks like the same kit. They buy in bulk using lower quality parts, allegedly. However if it comes with a good warranty then does it matter?
for what it's worth I'm going down the makita route. I have good good back up and good warranty. The only down side is I have demoed the makita stacking box. As far as I am concerned it is awful. A good concept that is fiddly to use. Will not be persuing that. Really needs a redesign. The wurth stacking system is much better. But that is off the subject.
it also depends on how much use you are going to give them. My neighbour swears by Ryobi, but he is only using it as a domestic customer with low usage. Read the Ryobi warranty. If the product is used for more than domestic work then the warranty is void. We are by no means high usage, probably medium usage. But the kit need to work and work well when you need to drill through steel.
i looked at Bosch, Hitatchi and Makita. I excluded Milwaukee because it was way too expensive and the volume I'm talking about would be far too much to pay. I haven't heard anything bad about them though.
3 a/hr battery's are being superseded by the 4, 5 and even 6 a/hr batteries so there are some deals to be had with the smaller battery. Also worth ensuring that the newer more powerful batteries will work in place of the smaller battery. Just a precaution but there have been noted some issues with one or two manufacturers, just can't remember who at this stage.