Ooooh, I always wash my material in very hot water before using it -- one bad experience of running colors! Yes, if you haven't washed the fabric before, use color grabbers just in case.... But, I always wash after I'm done. one end was probably on the floor while I worked on the other and I want it to be clean! Also, it brings out the threads that need clipping (after I've spent big time already clipping!!!!).
DON'T use a top loading agitator machine! or if you must, use it on "delicate" setting only. It is too rough (just think of the jerking that occurs). My happy day was when my old machine gave out and I got to buy a front loader. Better in every way.
The advice to reposition the quilt in the dryer every 10 minutes or so is so important! Otherwise you'll have "wet" spots that never got to the surface. Don't use "hot", use "medium".
I find that if I don't use a dryer my quilts don't fluff up like I want them to.... they have an unfriendly stiffness. One more reason to wash and dry the quilts.
I have a daughter who is a "neat freak" (also one child has allergies) and she washed the quilts I made my grandkids every other week on regular in an agitating machine. After 6 years serious wear became a problem. Hey, that doesn't sound so bad, does it? ;)