People on here say certain things about rollers and pressed tinnys.
I must confess I listened to the man who made my old 5.6 tinny when he told me how to set the trailer up. We had the same boat at work (Fisheries) and did the same with it. My old Mackay had 29 rollers on it and I was told to sit the boat on the trailer, tie it down as for travel and then get under it with a jack and adjust every roller so they could be turned with the same resistance as all the rest. He said the entire boat needs to evenly supported not just the keel. It rolled on and off very easily.
Apart from beach launching when the trailer got rolled into the sea on a rope all the rest off ramps the boat never got dunked.
Worked a treat, no deformation of the hull and was as good as new when it was sold 9 years later.
If it were me I think I would go for the trailer with the most rollers that were evenly spread under the entire boat that you could adjust as required.
Cheers
Chimo