Like Georg, there are many who are happy with Ozy, Mercury and Penelope running an old XP version of PwrSDR. I also would like to hear what people are running as far as XP versions of PwrSDR are concerned. I use 1.19.3.4 by W5WC and it is fine. Penelope 1.2 and Mercury 2.9 with single Rx. However is there a better choice? Cheers Dean.