I raced flat water (open) canoes both solo and tandem for a few years.
1st, how much dies he weigh? The J180/190/200 is the first consideration. Although there is only a 10lb difference between the ‘official’ weight ratings of the J boats, in reality there is more difference. A woman in the group who was 130 did significantly better in a 180 vs a 200 due to much more proper volume for her weight. Just saying, if your BF is light, you need to find a boat with an appropriate volume/weight limit or it will be tough to control and more unstable than a proper volume boat. (Savage river has their own naming system, but same idea)
On the other end of that spectrum, if he’s over ~220lbs total team weight (i.e him + pdf + water + all gear) then the “wings” of a J200 series boat start to get sunk to the waterline. This is undesireable, as the boats are designed to float on a 3x27" waterline (27" beam at 3" draft) but have a maximum beam of 4x32. If you’re sinking the wings all the way and have an effective 4x32 waterline, you will be significantly slower than a slightly lighter person who only sinks the boat to 3x27 spec. Also if you are at the 4x32 waterline you have no reserve beam to aid with secondary stability, so the boat will fall out from under you much more abruptly as you lean it over to turn.
Assuming you want to buy used the boat you get is very much up to chance and luck. Not many J boats sell in a year so that will limit your choices unless you have $4-5k for a new one. I got all my racing boats by searching Craigslist daily within an 8 hour drive of me for a couple months. That’s probably your best bet. Search boat brands (Wenonah, Crozier, Savage River, etc) , boat names (J200, J203, Jensen, DIII, etc), and related racing products like ZRE (racing paddles). or even just “Racing” or “Canoe” as many people do not know what they have canoe-wise.
i have paddled a few solo boats and here are my favorites -
Anything by Crozier Canoes. Crozier makes an incredibly high quality boat and is my favorite all around racing canoe brand. He’s been doing it since the 70’s or 80’s. Im not even sure if hes in business any more but damn Crozier boats are nice. I still own his ~1988 J200 and it tracks like a freight train. In calm conditions I can get 10 strokes per side with no correction and minimal swerving. He also made J201,202, and 203 hulls. The 203 is also made by Wenonah and other. It turns significantly easier than the 200 which could be good or bad depending on your course.
The Savage River DIII series. I paddled a friends DIIIX for a race and found it to be extremely fast. The nose is very skinny which means it jumps a wake nicely and allows a good vertical stroke. The stability was on par with a J203. The D series is still a design that gets changes on occasion, as opposed to the J series which have been the same for quite a while. Also if you have the Big Bucks, SR’s layup in TexTreme spread tow carbon fiber is the best looking boat material around and extreeeeemly stiff. (Also ~$6k!!) But damn it looks cool.
I transitioned from rec canoes to racing canoes to OC-1/2/6 to Surfski paddling. I spent a lot of time balance training in racing canoes and have pretty good balance overall. One thing I noticed was the long time OC paddlers (in my club at least) had horrible balance. The Ama means you just lean left when things get hairy.
A J boat will punish you quickly and repeatedly for bad balance. An instinctual brace needs to be developed early in your C1 career or it will not be fun. Warm, shallow water tip-over practice is your friend. J boats do not turn well unless heel’d over very far. Typically you are just a degree or 2 from the point where the boat falls off the stability cliff. You need a lightning fast unconscious brace burned into your muscle memory to be successful at J boat paddling
Last thought, my Crozier J200 had the factory seat bottom at about 7" off the floor of the boat. I cut it down to 5" and re-glassed the seat pedestal as my regular racing lake often got high winds which generated 12" short period wind chop. I capsized in 2 races in a row even with my good balance and had enough. After cutting down the pedastal to 5", it was a night and day difference in stability. Now I can get water over the gunwale and hold it there if I try. I have surfed waves in Long Island Sound up to about 18" which is insane in a tippy open racing canoe, but only because of the low seat.
I say this because there will be a steep and harsh learning curve if your Ama-butt is not used to a low stability boat. If he gets a boat and deems it terribly unstable, lowering the seat 1-2" will make a very big difference in stability.