i'm on the fence and you bring up some good points. My thing is that the carly app actually seems cheaper than the nt510 and has more funtionality right? 60 for the dongle and 60 for the subscription? Is there anything I'm missing?I have the schwaben branded nt510 (currently 25% off at ecs btw). As far as I can tell so far it doesn't have as many 'option' coding functions. But it can register/code new modules. It can do all the adaptations. Register new battery etc. the code reading and reading/clearing of stored codes is excellent.
My 2c is the schwaben/nt510 is more useful long term. If you want stuff like mirror folding or whatever coded just pay someone for a one off coding session. Paying $60/year seems like a waste to me. Plus you can use the schwaben like a basic obd2 scanner on any obd2 car. For basic functions that is handy too.