Yes Roger, if you are flying serious competition stunt, I think you will find the OS / Enya NV will be of significant value to your flying. The engine runs are more reliable, and easier to needle for consistency for both the Fox 35 and 40. Remember that I used Fox Superfuel for all my stunt flying which had 29% castor. I used the standard Fox NV for years but when I got really serious, I switched. With the single hole NV, facing that hole straight back is the BIG secret. Try it, I bet you will like it.
When I went through that mid-life, mid-40 crisis, in the split up, she got the gold and I got the shaft. She got everything in the house including all my albums. I have almost NO pictures of my many stunt jobs, especially my MIG design, with an actual swept wing but hidden by the large tapered flaps. I built 3 before RC. The first was excellent, the larger 2nd was superior in all respects and brought home a lot of loot. The 3rd, redesigned to be the ultimate was ONE BIG DOG FECES! [:'(]
Here are several pictures of one of my Noblers, Fox .35 early on, and some of my trophies in the basement of which 125 wound up in a dumpster. In addition I'm launching a Starduster 900 on a Fly-off flight to win the 1967 AF World Wide C FF event. That model also won the Chicago Aeronuts AAA Mid Western Championships, 1968, Bong Field, C FF. Yes at one time I was serious in CL Stunt, and FF for OHLG, Class C and some 1/2A.
BTW those 36s aren't really ported for the .35 type stunt run but a small restrictor in the venturi will help. I run one in a STill Stuka, but it ain't very much to my liking, however the grandkids do OK with it.