A few pics!

https://cimg6.ibsrv.net/gimg/www.off...69b57629f6.jpg

My first Donzi and tow rig. Circa 1998
https://cimg2.ibsrv.net/gimg/www.off...a8a801d29.jpeg

12 years later, same colors just larger! Totally not planned, just happened. LOL
https://cimg8.ibsrv.net/gimg/www.off...6757b062dc.jpg

Moving our big old dinosaur!

Diesel Dually, way to go for sure. I tow my 41 sport boat and trailer 11500lbs plus with 3/4 dodge cummins 6.7. The boat can push the back end around when you hit 70mph. 10ply tires. My last boat was a 32ft, when i towed that i didnt even know it was there. I think with lower profile tires/taller rim it wouldn't be as squishy. 65mph is np. I tow at 70, when i come to a curve i slow down. I like the srw only because i can get it through the car wash. Otherwise Diesel Dually hands down for 40ft or more. Dont bother with gas. It will just eat fuel, downshift on every incline and make for an unrelaxed stressful tow.

I tow my top gun with a 2017 srw ford 250 with hevy tow pakage , basicly a 350 ,with 250 badging . don't even know its back there . well maybe a little . lifted on 22 and 37 inch mt toyos .aired to60 psi . just saying . no need for a duelly . I have both . duelly is better of course . but not and issue . duelly also has to inch kelderman air lift on all 4 corners . and 37s also ..

Assuming you are towing with an "every man" truck, for which I will describe as a 1-ton (SRW or DRW) from Ford, GM, or Ram...
...a 37'-42' V-bottom is just about the right size boat in length, width, and weight; to be very versatile/suitable in almost any boating event and still be reasonably easy to tow AND maneuver/launch/retrieve at marina facilities...
...for your AVERAGE recreational towing adept person. (Meaning: someone who tows professionally would be more comfortable with bigger).

There are SO many caveats though, and even my comment above about the professional driver will not overcome crappy ramps with short approaches, or short ramps overall. The trailer setup matters. The boat design matters. (There are places you could launch a 42' Cigarette or 42' Fountain straight or step bottom easily, but could not launch a 37' Active Thunder, all because of the big step on the AT had to float up 4" vs. just slipping off or floating up only 2" to clear two, 2 inch steps.) Some ramps have steep transition angles from the parking lot, whereas a long trailer will high-center. The Miami Outboard Club ramp has a HORRIBLE transition as an example. Some folks also have customized/spec'd their trailer with the ability to drag the front axle back up onto a short ramp, by having some structural steel/aluminum angles welded in front of the axle. But that may also impede curb hopping, which inevitably always happens at some point with a longer boat's trailer having the axles so far back.

Looks like general consensus is 42ft performance boat. Shorter if taller and beasty.

I tow my 36 Outlaw with a 2017 Ram diesel 2500 single rear wheel. No problems towing around Pittsburgh or over the road. We do tend to plan ahead using google maps/earth when planning gas stops. Fortunately, most truck stops and gas stations along the highway are large enough to move a trailer around easily.

You can also launch a 42 single handed. I do it 80 percent of the time unless its windy but if your trailer is set up to drive on, probably easier

I launch and retrieve my 38 regularly. Just takes a little practice, and Good trailer and a Beer or 2 :lolhit:

thats purdy