I'm a pretty big guy (6'2", 220 lbs) and have trouble fitting into the smaller sprint boats. The Vanquish XXL works pretty well for me. The boat has enough volume that I don't feel like I'm sinking it. And the above-water flair of the cockpit gives me adequate room at the hips. Foot room at the the tiller bar is still tight, though, with my size 13 feet. Even with bare feet, sharp turns are a bit of a trick.
The Nelo lives up to its reputation as a modern high-performance racing boat. It's at least as fast as the old-style Eagle-2 that I owned previously, and not nearly as tippy. I routinely use it for workouts, and find it reasonably comfortable for an hour paddle. I'm not actively competing, but I've raced it in some division-level events, and was very pleased with its performance.
The finish is pretty delicate. I've gotten rather too many scratches on it after a year of use.