I'm currently working on a diffuser for the 335 m-tech rear - I'm really keen in developing something that will fit the stock rear though based on the interest shown here. I'm going to find a development mule in my area and see what I can do to get something out quite quickly (quickly being relative - it will take around 6 months)
I'd have to look at making a few options available:
335 vs. non 335
335: Dual / Quad openings
non 335: Similar story - opening on the left or both?
Give me some ideas / comments and I'll see how quickly I can get started on this.