^^ Present wheels have just a free hub so it was just a case of do I replace the rims on present wheels and just keep the free hub or get a new set with a flip flop hub instead?
Unless you need a fixed sprocket I'd reckon on a free hub being better than a screw on free wheel. Without pics or some proper detials of your wheels and bike setup it's hard to give any suggestions, but basically I'd probably just rebuild the wheels if they had decent hubs or just buy a new set and keep the hubs in a parts box for spares.
^ Nice. Do you have a pic of the bolt on side?
Unless you need a fixed sprocket I'd reckon on a free hub being better than a screw on free wheel. Without pics or some proper detials of your wheels and bike setup it's hard to give any suggestions, but basically I'd probably just rebuild the wheels if they had decent hubs or just buy a new set and keep the hubs in a parts box for spares.