My mate got his RNS-E unit from the same guy. Top bloke & packaged very well, and yeah, you got a good price there.
Check out my RNS-E thats up for sale.... http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=170488496072&ssPageName=STRK:MESELX:IT.
I'm selling everything needed, so from what you've bought you'll need just the Plug&Play Harness & Diversity Antenna and the removal keys if you havent already got them.