Hi Martin
If your OTA can support a full frame sensor rather than just the APS-C size sensor, you may find that in a year or two, you hunger for the 35mm full frame sensor which would mean purchasing new 2” filters, making the 36mm ones redundant.
So, how likely are you to upgrade to a full frame camera?
I have a Tak Mewlon 210 which copes with the QHY268M (APS-C) and CFW3 36mm unmounted filters, but the coma at the edges will not tolerate a full frame sensor.
However, if my OTA was suited to a full frame sensor, I would probably have felt the urge to upgrade by now, which would have made my investment in the 36mm filters somewhat limiting.
Generally, finances, etc. permitting, I have found it better to reach a little bit higher to allow for space to grow into the equipment to meet future needs as they unfold.
Good luck.
Cheers
Dennis