This video reviews it pretty well. It appears to be slightly more "polished" in general than the 3.3, with a metal carb that tunes easier, runs cooler, and produces comparable power. Here's a video of that guy running it.
Every external feature like the crankshaft, starter backplate, and...
Something of a common experience, it just appears to be the limits of that carb. Maybe it's a deliberate feature so the engine always starts with an EZ-start, but yeah, difficulty getting the idle down with the stock carb is a common complaint. An OS 11k carburetor is the Rolls-Royce of carbs...