The off-the-rack speedo can be a bit too confining.
I agree speedo brand speedos feel very tight to me and don't seem to have hardly any room for the "tackle", and tyr suits are about the same and the fabric feels very thin.
Currently I wear a Nike brand speedo, recently I've just been going with plain black, I know its not that exciting but it doesn't really show a bulge and doesn't attract extra attention when i'm wearing it in places where most guys aren't wearing speedos....
....there sizing seems to be more on the bigger side, Im like a 32/33 waist, so I usually wear a size 34 for general recreation wear, and if Im going to be swimming laps or something for fitness I'll go down to a 32, and if I were to get back into racing I'd probably wear a 30...
...that could be why I own speedos in every size from like 28/30 up to like 36/38, ...
...since I wore a size 36 recently when I had a job requiring swimwear and I was going to be wearing the speedo for like 10 hours a day during times when it would be wet and dry....