Master of Towing Equivilancy

With a Master of Towing are you able to operate as an OUPV or a Master Inspected vessels or are you limited to towing vessels only?

It is a different qualification. You have a license. 25, 50, 100, 200 ton. Whatever. With that license you can operate any boat that falls under the tonnage listed. However to run a tug you need the additional master/mate of towing endorsement.