Just had a substantial pre-bike purchase fit (measurements, video in various setups,etc) with a recommended local fitter. The only downside is that the shop he's affiliated with is limited in brands, combined with the general supply chain constraints/excess demand in the industry right now, how would you recommend proceeding?

Ideally I'd just purchase from the shop with the good fitter, but it'll be tough in the near-term. I've got a variety of figures that I think would translate to other frames, but given how much things can impact each other with minor differences, what's the best way to be sure if I went and snagged a frame elsewhere for instance that it is good enough? I suspect the fitter will be helpful to some degree, but I also realize their job is done/prefer to focus on in-house brands.

Guess I should have asked that before the fit, but he just was so well regarded that thought it was better to start with a good fit, then find a correct frame.