One of my favorite type of rocks, personally is Marshall Island...but it is a bit more $$, and I haven't seen any here at the LFS. So for my small tank I got Marco Rocks, which are dried Fiji rocks....but you would not be able to tell that 3 months ago these things were white....
For my 220 gallon, I just finished purchasing 200 lbs of Walt Smith Fiji. A LFS here ordered about 2,000 lbs of the stuff....and it came a day late...so because of that extra day and extra die off, he gave me a GOOD price on (4) 50 lb boxes.....
So all those rocks are in my garage curing. I am hoping to have my tank up and running in the next couple of months....I am finishing up my stand (hopefully this weekend, stain it, and then probably bringing it in the house and aquascaping and letting it cycle.
But I digress, Marshall Island is VERY good looking rock...but Fiji is also nice and a little more cost effective....