Probably better off in "Sailing" forum.

how big and what type of boat.

After my cheapo Whitworth's inflatable fell apart after 2 years I had a Tuff Tender on my 15m yacht and it had definite pros and cons;
I had an overhanging transom....I suspect that a sugar-scoop transom would suit a Tuff Tender far better.

PROS
Essentially indestructible.
Very stable when in the water and brilliant for fishing.
Gets up to plane with a 9.9HP and 2 adults.
Cheaper to buy than quality inflatable.
Lockable storage lockers on the one I had.
The oars, life jackets, anchor etc fitted inside the hulls, via the locker hatches...out of sight of light-fingered scum prevalent around marinas
CONS
Heavy to lift up on davits....when loaded with outboard, anchors 'n stuff, 130-140 kg difficult for one to lift unless using multiple blocks or unless electric winch used.
Heavy duty davits will be needed. Extra cost
Trimming the yacht fore and aft will be necessaryas the waterline at the stern will be down!
Difficult to get it onboard midships or forrard to stow on deck due to weight.
Difficult to lash securely whilst on the davits as it is slightly flexible....the tighter you lash it the more it distorts.

Bottom line for me? Just a bit too heavy as a tender and I'd probably save up to get a quality rigid hull inflatable.
As a small dinghy around canals, waterways, marinas and lakes the Tuff Tender was great tho'!