The improvements in recent updates, specifically concerning track-based navigation, have tempted me to reinstall MRA Navigation again after a long time. In theory, this is exactly what I was hoping for when MRA Next was first announced way back when and for the most part, it works quite nicely. Good stuff!
I've tested it over the weekend on a route I know quite well, where I made a couple "mistakes" on purpose to see how the system would handle it. The basics went quite well, but I did encounter a few issues.
The first issue I encountered is that the route I had planned (using the web planner, on the TomTom map) had already changed when I viewed it in the app, because of a ferry crossing (which we know HERE doesn't handle correctly, it tried to send me around adding 30 minutes and 20 kms to my trip; yes, I know there's a work-around, no, I'm not going to use it). So, sadly, it seems I'm still not able to trust that my planned route will not be touched when using it for navigation, even with track navigation, which is one of the main reasons I don't want to use route-based navigation for planned routes (simple A-B is fine, of course, but that's not what I use MRA products for).
The second issue was that I (on purpose) put a Via-point on one road and then (again, on purpose) used a different road. The good thing is that the system (with recalculations enabled) handled my deviation quite nicely: recalculation was quick and suggested a reasonable alternative route. Obviously, it tried to send me back to the missed Via-point (as expected). What I did not expect, was that I had to skip multiple waypoints to get rid of that. As I did this while driving (yes, I know I shouldn't have), I didn't notice which point(s) I actually needed to skip manually (automatically skipping waypoints is enabled in the app, not sure if it affects track-based navigation?). I got the impression that it may have been asking me to skip all points (including shaping points) from the start of the route and not just the via-point I missed, but it could also be that it somehow didn't correctly register that I wanted to skip the via-point and just kept asking me about the same point multiple times.
A third, completely separate, issue I've noticed on a few occasions, is that I get a notification that the app has crashed after I've used CarPlay, but I haven't used MRA itself). I'm using the latest iOS version (just updated to 18.2, but also noticed it with 18.1) and the latest beta (haven't tried it with the official release yet). I've had this before as well (with way older versions). I've mostly been using the betas, so it could be a beta-only/TestFlight issue.