I've been running the DLE20 in a 1.10 class TWM SPot on all of last year. I retired the airframe the beginning of this year to fit it into a H9 SHowtime 90. THe Spot on was simply poorly constructed and after a few mishaps showed age and an marked increase in weight.
The DLE 20 provides fantastic throttle responce and instant spool up on an APC 17x6. I've run various pipes as well and am achieving 8400rpm on the ground with a canister.
My next gasser Pattern plane project will be an Evolution with the Mintor 38 on pipe. The OS GT33 is the back up plan.
I don't think theres going to be many petrol pattern planes at the Worlds in 2013 (to be held at 1600m above sea level) but I believe it will become more widely accepted thereafter.