I'm 6'0 & 185lbs. currently surfing a 6'4 thruster with a thumb tail. Don't know if i want to go more than four inches or not over my height...
Smaller waves i use a 5'11 & 6'1.
im pretty much the same height and weight and i usually ride around a 6'3" or 6'4" for anything around headhigh+.
i ride a 6' dumpster diver for smaller surf.
i bought a 6'8" rounded pin step up for an upcoming trip and got to take it out earlier this year in 2-3' overhead surf and it was a gem. i felt it held better on a bottom turn than my regular thruster, but was able to turn really well just like my thruster on any kind of snap or turn.
there are all different types of OH surf. At 6'-185 lbs. I can ride a 5'6" board at one location OH, maybe a 6'2" thumb at another, and maybe a 6'6" at another. Is it hollow, mushy, out-bar, point, jetty, shore break etc? Are you towing/stepping off? Then we can go w/4'10" quad.
Call me crazy, but I like riding a 5"11 roundtail in overhead stuff around here. I mostly hit up Assateague on the big days. But I've also used the same board down in OBX and St. Augustine in overhead stuff as well.
Just like I like my women - short and fat. 5 10 x 2.3 for overhead, gets smaller from there. Sometimes I feel like people get really concerned about what they ride or what they should ride in bigger surf. If ya got it, FLAUNT IT.
Yea... the kind of wave is a factor. The spot, the wind, the tide ESPECIALLY... are all factors. Then you have your "personal preference" factor, which confounds the issue even more.
But generally speaking, up here in Mon Co, NJ, most of the spots get fast and racy when it gets big. So you want something that matches your level of comfort and skill. I'm an old man... 46 years old... 6'1" and 190lbs, and I don't like to get worked if I can help it. If it's 1 or 2 or even 3 ft. OH, I ride a 6'6 round tail convertable quad/thruster, single to double concave. Just typical performance shortboard design.
But when it approaches DOH I have a 7'0 East Coast Gun (like a step-up) designed specifically for our thick, heaving, local beachbreaks. Surf like that is most often generated by Nor'Easters, which are followed by hard NW winds. So that board is designed to handle hard offshores, lots of current, and fast, hollow waves. Plenty of rocker, a fairly pulled nose, rounded pin, vee in the entry to flat to deep double concaved vee, to flat behind the trailing fin. Very similar bottom to the original "Black Beauty" but without the chined rail. Just a modern performance shortboard rail with a soft tucked edge that's hard only from the rail fins back.
Just for comparison, when it's in the head high range, I ride a 6'4 quad. Waist to chest mostly a fish. Under waist high a single fin longboard.
5'9, 160. 6'2 is what I ride up to DOH. I wont ride over a 6'2 unless its really big, then I jump up to an almost 7'0 mini gun... the 6'4-6'5 range makes for easy takeoffs, but is too sluggish for my liking... Thats just me though.
So, while my normal boards are 5'11, and 6'0, 6'2 is my step-up board, cause it still responds the way my others do.