Personally I perfer the boys. Mine seem to want to play and run around all the time, where as the females can be like "what are you doing in MY cage?" I open the boys cage they're out playing, I open the girls cages, nothing happends.
As far as spraying goes, the only one who sprays me is the one who is blind. I think she has permanent PMS. Once I pick her up shes fine, out of the cage- fine, but in the cage with my hand offering her a treat/stick get ready for a bite or shower. It has been that way since day one. She doesnt run from me, sometimes wil even seek me out if Im giving a cage mate a scritchy. She just has to make all the moves.