Yes, I run the -30.
Yes, I run the -35.
I have both because it is worth the trouble changing them for different riding areas. Going to the sand (coast? glamis?). Rejet, strap on the -30, retard the ignition timing. Riding in the woods? Rejet, strap on the -35, change the timing back.
Last time back from the sand I figured I'd give the -30 another shot in the woods with my 'new' DFII. I was surprised to find that it worked! THEN I set the reeds to low tension......and it worked even better! I've got at least as much on the bottom as I had with the -35, and like I said, the -30 can be a blast!!
There are some tradeoffs (wow. THAT'S a surprise! ;) )
Woods riding with the -30 has a larger 'wear out' factor than the -35 does. Throttle control becomes very important. The hit of the -30 is substantial..even with a FWW. Your shoulders will likely feel like you've been trying to pull an arctic cat quad out of a ditch with a rope all day!
That's what they make advil for!
The DFII is less $$ than the pipe, given average retail, by about $30. The DFII is a great compliment to either pipe profile. Keep your -30 and give the DFII a shot, imo. If you don't like it, keep your -30 and buy a -35 so you'll be a good boy scout (prepared!).
...and repack your silencer (if you have a packable one) while you're at it!