I bought a 337 and love it. Excellent bow, excellent quality and excellent performance. The 337 sounds like exactly what you are seeking. It is very smooth and very quiet. You state that speed is cool but not what melts your butter. I agree. Just because there are faster bows made doesn't mean Ross is lacking in speed. They are fast bows. It's just that there are faster bows. One should try to get the most performance out of whatever bow he has.
There is only one fastest bow. I don't know which bow that is and I don't care. If you are after speed, Ross has it. If you are after the fastest bow made, I don't know if it is made by Ross, Matthews, Martin, Bowtech, Jennings, etc., etc., etc. Frankly I don't care. I own a Ross, a Mathews and a Bowtech. I'm confident that my version of each of those manufactures' bows is not the fastest. I do know that each one very effectively terminates the life forces in both big and small game.
I know that's more than what you asked for; but, my Ross 337 is my favorite of all that I own and will be accompanying me on my elk hunt starting this Saturday. Good luck with your decision.