This is the same story as my kitchen knives lol. Spent way too much on a fancy chef knife and the $20 one from the restaurant supply store gets used every single day. We convince ourselves the expensive thing will fix something in us, not just do the job better. Turns out half the time we're just paying for the story we tell ourselves about being serious about our craft. The teflon folder being the real workhorse while the bone one sits there looking pretty is basically a life lesson.

The mask helps a ton but it's not really fixing focus by itself, it's just letting you see when focus is off. The real win is that you finally had a way to check it, so you stopped guessing. I chased the same thing for way too long, stacking frame after frame, when my stars were just slightly soft the whole time. One tip though, the mask gets you close, but do a final tweak on a bright star at high zoom without it, since the spike pattern can lie to you a bit on some scopes.