I'm using an AC110 on my 46 bowfront...plenty of flow, and the fish love to play in the "waterfall". I'm also moderately planted, but since I've never used another system I don't know if that makes a difference, my plants seem happy and green. As for surface turbulence, if you keep the water level up to the output, it's minimal, but if you like a couple inches of leeway (like for breeding snails), you'll see a lot more agitation. You'll see that with any HOB filter.
