Sorry, the very night I posted that I'd gotten it, an ice storm (freezing rain) blasted through here and dropped trees down across power lines all over Boyd county. Lights went out about 10:30 pm that night and didn't come back on for two days.
Not following you on the "Sumpter" ride report. Do you mean as in Sumpter, South Carolina? You may have me confused with someone else who just got one,...I'm an ol' Kentucky boy,...Geez I
wish I was in South Carolina right now!
All I've gotten to do so far is a couple of 'break-in' spins around the two lane blacktop backroads. I can tell you that at 60* F./600' above msl, after she's warmed up good, she carburets pretty cleanly. And that's with 32:1 "break-in mix" too. It's drooling a little spooge though.
I personally have not seen any of this horrible, ill-tempered, Dr. Jekyl/Mr. Hyde "hit" that the Aussie mag reported. It'll lug down low on the bottom end, and transition into an awesome mid-range that'll put a goofy grin on your face, with very little throttle input, in a very linear and contollable way. It's maybe not as "electric" feeling as my 300XCW is,...but it's certainly nothing to be intimidated by.
I was climbing a little grade on the road out front the other day and grabbed 2nd pretty hard at about it's mid-range, and it just voluntarily carried the front wheel about a foot high for about 10 yards up that slope without any intentional input from me for it to wheelie. That made me smile and pet it on the tank.

You can feel that it's gonna be strong just dumbing around the house here with it. It's plenty stout but all it wants is a little respect and some throttle control.
Haven't seen the extent of it's top end yet, 40 mph is about all I've had it up to around the neighborhood. Trying not to wring it out just yet, and also trying to draw as little attention to myself as possible from the Po-Po,...and those who might call the Po-Po if one was becoming a PITA.
By the time it warms up some around here I should have it prepped and ready for a good trail test.