Mike,
I would stay clear of them, solely on the basis that they never were a big deal outside Scandinavia. I can only recall seeing one here in Australia in my ISSF days, though it did win the first ISSF world cup contested on the best 10 shoot off system, if my memory serves me correct. There will be no information on how to set up, bed or tune it, all the stuff you'll want to know.
Once you get that crap in your brain that you're cutting corners or using second best, it erodes your shooting confidence.
John