Hi Dento
I certainly don't want to denegrate SBIG cameras as they are indeed fine instruments in their own right but the argument that the patented self guiding is such a bonus is a little over rated in my opinion. There are countless examples of piggyback guided images (like Alan Chens M45) that were taken using a seperate guide camera and guide scope, to clearly counter this percieved benifit. With a decent mount and well mounted guide scope with a rigid focuser, self guiding is just not necessary unless perhaps you want to take long sub exposures (in excess of 10 min) with a very long focal length scope (> 2500mm) and even then it wouldn't be impossible for piggyback guiding to return good results.
The myth of the importance of self guide was born from commercial Schmidt Cassegrains with floppy mirrors. If you are using one of these then self guide is very useful but otherwise it is over rated IMO.
Mike