I used reef rocks about a year ago for my 75. I got their sand and 50 lbs of rock. Rock took about week or a week and a half to get there and about a month for the sand. I wasn't setting up the tank for about a month when I placed the order so i was satisfied. The rock is porous and easy to aquascape. The sand is a little to fine but looks great and has lots of little shells in it.
With all that said when I wanted to add more to the 75 and get some rock for my 24 gallon I went with marcos. Why? Communication is terrible and you will have no clue when you are going to get your rock. I needed rock for the 24 within a week marcos got it to me in 3 days and shipped out the day I ordered it.
This is also pretty consistent check their vendor forum on RC:
Reef Rocks - Reef Central Online Community
The rock and sand is great but be prepared to wait.