Finally gave in tonight. Been wanting an STI for about a year now so I took the money I got selling off my V1 + a little extra and bought one. Got the last one this particular truck stop had. Production date is a 3607.
The STi display is visible when mounted above my mirror where the RX65 wasn't, so I'm going to move up to there and install the amplified speaker tomorrow.
Had one verified 33.8Ka alert on it, detected it pretty well. Ramp up seemed fine to me, but I'm used to the Bel stuff and not too picky about audio ramp-up. As far as I could tell it's pretty similar to my S7 RX65.
I'm very pleased with the construction quality. I'll post experiences as I have them. It'll be interesting to see if it can best my RX65 for Ka range, because it's always been amazing.