I have some BRx5 units. They are great! I have a couple other sets but I go for my Carlson every day if I can. I now have an external Topcon SRL-35w radio hooked up to them for some range and to get into some tough places. I think you can get a base and Rover setup for 8 or 9k. We've been thinking of buying another set or getting the BRx6 unit.
I also run SurvCE 5 in a ranger and Carlson Surveyor data collector with the units Can't beat the Carlson tech support either.
A couple months ago I had my brx5 base taken out by some horses. I was about a mile away from Base when it happened. Not having any idea what happened it went to autonomous. About 2 minutes of me scratching my head it fixed again. Maybe the horses kicked it enough I don't know. Anyways I was clearly out of my stakeout position. Went up and found it knocked over beat into the dirt. Anyways I was impressed by the beating it just to took and still capable to work and give me fix knocked over.
Dont know what kinda specifics you are looking for but I'd buy again and I use my units just about anywhere.