I normally go with a max of 10 meter dif every 2-3 mins for circular problem will be following the things around the planet for 2 orbits as when you decouple parts they get they own speed
http://www./?35teuwoma38kola it does use a quad and tri coupler and a small srb from wobbly rockets to deorbit, but it should lift 2 http://www.kerbalspacerepository.com/2011/07/17/stellarcom-communications-satellite/ in to a high orbit