Im sure there is a difference in grades of micro-fiber but I got mine at a whole sale club and it works great. My wife bought me 4 more bags. I have enough to last me another 8-10 years. Great investment.

 

There's a huge difference. The nicer ones (ie; Gold Class) will be much better at preventing swirls by trapping any dirt/grains in the nap. Also, some of the cheaper ones have a cheap backing, so while the nap is nice, the backing itself causes swirls. Make sure the MF's you get are deeply piled.

As for washing, don't forget to use a liquid detergent; I fear that a powder won't completely dissolve. Also, after washing, consider the place you fold them and store them. Mine live inside of a plastic bin, and the Water magnet, Gold Class towels, and a slect few other ones are in ziplocs inside of the bin. This way, there's no dust on them that might cause swirls, and if I drop them, they don't have to go to the wash; they're protected by the bag until use.

Lastly, I reccommend getting several grades of MF towels. You won't want to use your nicest one on a any dirty part of the truck. Keep a few dingy ones for doing engine bays, weather stripping, etc. Keep some moderately dingy ones for wheel wells and lower parts of the truck. The nicest ones should be used on the hood and upper parts of the body.

 

I agree Windows, wheels, lower body, upper body, bed cover, interior, inside windows, all use different MF towels.