OP stated in another comment that their budget is at least $1000. They also stated they are interested in a higher variety of filament. That points to the P1S being the most fitting of the Bambu lineup.

The ‘closed source’ argument is really up to the individual. Personally I’ve found no real issue with it or any real evidence that it’s a real concern for the future. The only real downside I’ve seen with Bambu is some bad experiences with customer support. However, I believe that’s a risk regardless of manufacturer.