Back in 2002, I got some RV transition training as I was finishing up my RV-8. I'd gotten some hours with Mike Seagar in the factory 6A, but had never flown in a tandem or tailwheel RV.
The guy I sweet-talked into taking me flying in his -8 was a crusty, retired Continental pilot who had flown everything from C-47s to 747s, and had a huge hanger filled with all kinds of airplanes.
"I'm not signing anything!" he growled, and I assured him that all I wanted to do was a series of stalls and landings, just to get the feel for it (from the back seat anyway).
"You're paying for the gas, right?" And after I assured him that I was good for it, we walked out to his -8.
"Do you want to know how much tailwheel time I have?" I asked.
He grunted as if he hadn't considered the question and raised an eyebrow as a affirmative.
"I've got about 600 hours in my '46 Aeronca Super Chief (11AC) with a 65 in it."
"!$&*(@$&*," he shouted, "That thing is the worst $*(@)$^ airplane ever $@^&^%! built. You won't any problem with an RV!" and he turned around to head back to his hangar.
"Uh, can we still go flying. I'd really like to, uh, you know..."
"You're still paying for the gas, right?"
That was eighteen years ago and I don't even know how many landings (good, bad, indifferent and one perfect one that nobody saw). I've flown (besides the 8) 4s, 6s, 7s and my neighbor Bill's 3. All are as honest as the day is long...
The biggest difference IMHO is between a fixed pitch vs a constant-speed prop...you'll need manage your airspeed more closely with a fixed pitch...as the c/s unit allows one to 'cheat'.
BTW - I asked the guy who I flew with which airplane he had the most trouble with landing, and he surprised me by saying it was his C-150 tailwheel conversion...FWIW.
Nick "Hairball" Knobil
RV8 N80549 (First Flight 2003)
Aerosport O-360A1A, Dual LS CDIs, WW200C