If you really like the sound of ARC, why not look for something from ARC? You know what type of sound to expect. But before I buy anything I would still want to hear it in my system. There are differences in the sound even from units by the same manufacturer.
If I wanted to try the BAT, I would tell the dealer that I live quite far away. Ask if you can demo the unit for a week. If you like it, then just keep the unit and call the dealer with a credit card. If you don't like the unit then return it. That way you don't take the chance of being stuck with something you don't like.
IMHO though I would rather buy a piece used than a demo. Demo pieces are usually left on for long periods of time so that they are warm if a customer wants to hear them. The other thing is that a lot of people have taken the demo home and played around with it. People tend to take better care of something when they own it compared to when they just borrow or rent it. But this is just my opinion.
I am a big ARC fan. I own an LS25 mk2 and Ref 110. I have also owned a Cary SLM 100 and have had a couple of CJ pieces in my system. I liked both the CJ and Cary but the sound was a little more tubey than ARC. I have also heard a BAT system at a dealer. The sound seemed more like my ARC gear, both use the 6H30 tube. But it was at a dealer that does not loan out gear. I would still want to hear something in my system before I bought it.