My experience with them has been a relucatance of decision making, decision by committe, decisions that might have to be made by multiple lenders, bickering between lenders, agents that could care less, listing scams.....on and on. As I said, I see this from both sides - both as an agent trying to move them and as an appraiser trying to get them ready - they're typically chaos for all involved. I have had a few from the buy side go OK - did two in 15 days with Bank of NGA in December - end to end which was great. Other than those, until there is a set method instituted for lenders to follow with some degree of consistency, I don't see these being anything more than exhausting.
Something else sellers need to remember is that it's not typically a "win" for them - they may be subject to collection of the unpaid loan, tax consequences or more. Getting the home off their hands is just a part of the mess.