yep, the switching regulators are a lot more efficient.
http://www.robotgear.com.au/Product.aspx/Details/464 is pin compatible with the 7805's.
I'm also looking at multi channel solutions like the RC servo's, so you can have just one transceiver and multiple endpoints like focuser, finder, scope, camera. aim is to have the whole thing wireless using BT or wifi, atleast for me.