The new Hilti is the TE 7A 36v lithium – around $1800 new in Australia. I now have one of these and it is the shizzle. Worth the money if you are going to do a bit of bolting.
Bosch make a 36v – around $1200 in OZ-would be great im sure
Probably the best drill close to a $1000 is the Panasonic 24v, I haven’t used one , but quite a few guys i have talked too reckon it is a really good drill for the money.
I wouldnt go anything under a 24v and at least 2.6AMPH.
Dewalt-make a 24v , not fantastic
Hitachi- Make a decent 24v, with a really good percussion, not sure on the $
Bosch also make a few 24v’s- I have the Platinum, which was $1000 with 2 2.6amh batteries. Great drill
GMC- Make a real cheap 24v. you get what you pay for!!, not very good percussion, battery life or grunt. Basically these drills are meant for young limestone not granite!, NOt recommended
So in short, if you have the cash get the hilti TE 6a or TE 7a.
otherwise get the Panasonic 24v
hope that helps