From those numbers, the 21 foot Skeeter gets you 4 inches of length on the front deck, and 2 inches wider at the consoles than the 20 foot lynx.
The Lynx has an inch more of beam. Its also carries 15 gallons more fuel.
If a speed limit is not imposed, you can bump up over a 250hp on the Lynx. The Skeeter is limited to 250.
The most important thing in my opinion between the two boats, at 45 mph, in big water, would be the depth and design of the bows. That would play a huge part in its ability to plow water smoothly, stay dry at low speeds. The stability when the TM is down would be close, especially with the 96 inch beam of the Lynx.
As for the OP’s question, Priced comparatively, it would be the FX21 and the Lynx. Not the Cougar or Puma.
The ZX250 series is priced toward the Advantage series Cougar. The point your actually making.
Of course the numbers are the same for that model Skeeter also. Definitely a good value with the SHO.