Nothing wrong with manual windows. In fact with electric motors and regulators no longer available, so only used (poss worn out) ones as replacements, if yours do fail, manual ones are so much more reliable. I think VW had this in mind when they used the same door card with the winder hole in it for both manual and electric.
If I were you, I wouldn't be rushing to sell your electric set up. Granted, it may be worth a few quid, but in the future you may just want to put it back to original. Every original part that gets changed on my car gets packed safely away, as I reckon in 20 years time, I just might want to put it back to the spec it left the factory with.