i no longer use UDI and insteon due to me switching to Control 4 and Ra3. I wouldnt sleep on the marketing. The increased speed from when I used insteon, zwave, and hue with Polisy was noticeable (programs). That alone made the change worthwhile. Had EISY supported Ra3, I would've used that instead of C4. Additional note for those that may read this: EISY does support RA3 dimmers, switches, via caseta node server.
Insteon I3 devices are worth switching to if starting fresh with insteon. If Ra3 never came out, I would've been using those. They are much higher quality when it comes to look and feel compared to the old ones. I wouldn't rip out my system to use them though.
With that said, since the speed difference and other technologies are irrelevant to you, I don't see any reason for you to swap from one to the other. I know they've started on a new web based interface but I think that's only for beta testers right now.