I have had CoachNet for years and have always had good service.  One thing to watch out for, though, is that if they send a mobile mechanic out and he or she can't get you going, they will not pay for a tow.  For that reason  I have always opted for the tow unless I am 100% sure that the mobile mechanic will work.  I am pretty sure that Good Sam and whoever FMCA is hooked up with now are the same.