I like the inflatable as a tender,but I tended to keep the sailboat anchored and used the tender to explore,go diving,and run errands.I have had it 8 miles offshore to a reef with 4 people and snorkel gear,cooler etc....A Zip might have done that with the higher sides than the TNT,but the inflatable is more sea worthy in my opinion.
The plywood boat will do all those things also, but isn't as sea worthy in rough water for diving,snorkeling etc
An open Zip will have a little more capability in rougher water than the one I built, but you still have to watch it some.
How will you stow it? Davits? Towing?These are all things to look at.
I towed another 14'boat I had behind the sailboat once, and it put a heck of a drag on it.The inflatable towed the best,although the TNT wasn't too bad.I bought davits finally and oped up a new can of worms as well as solving some problems.
This is towing the TNT at a slow speed
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TNT as dinghy.jpg [ 262.79 KiB | Viewed 624 times ]
If I ever get back into using my sailboat,I'll buy another 10'Caribe RIB and use my 18HP Tohatsu on it.