Perhaps I don't have a direct comparison, but I do own a H/L Time Machine that I purchased spring off 2017. I didn't know what I was looking for exactly at the time but I was at the boat show and knew I wad looking for something different and better than my Rocket. Lucky it turned out to be a nice board, and I found it to much easier to stay on the wake with than the Rocket. It's a very similar shape to the Quad and shares the same fin configuration. I'd have a hard time saying anything bad about it.
The only thing I could say is that like your quad, I know it would be less than effective on an underdeveloped wave. I think that's what makes the superior to a degree. It can manage a smaller wake scenario, but becomes increasingly effortless on a better wake. Effortless = freedom = fun. You have the freedom to play around on the wave without so much worry about keeping up. A 200 lb guy can be 20 ft back and glide right back into action.
I'm not so pretentious to say it's the only board that can do it that, some of that is owed to the fabulous "Gantlin Wake". You mentioned in your other thread how far back you or your wife could come back from... it just might be that much easier with a Coaster...?
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I think your question about boards has evolved with your wake from, "what board will work with my wake?" To what board to I want to ride on my wake?"
That's where these boards might vary a little more from each other. The profile of the quad you'll notice maintains a straighter line front to back. Where as the Coaster is almost a continual arch from pintale to the pointed surf style nose. The pointed nose is going to be a little more forgiving both entering and exiting the wake and the roundness is going to help you roll and rotate the edge of the board a easier. The fins I think are doing a lot more driving on the quad and they say the shape makes it "poppy".... and more smart stuff... lol!
Am I rambling?