I was thinking about how the specific implementation of the double belt, wondering if the round profile of the HDT 3M belts would even agree to do what I want to use them for, when I realised that I'd need 8 bearings for each slider that used the double belts. I could probably cut that to 4 if I printed out some kind of wheel, but the total amount of bearings still exceeds the 200 I have now and I don't have that much space in the sliders.

I did the calculations of the main bearings and I got 224 bearings for both Sublimes. I feel like I must've accidentally only calculated for one set in the past. Anyway, it's not like I want to take a chance on a 3rd set of bargain bin bearings that would probably go out of stock forever in the coming months, especially since I'm trying to get some sort of decent system everywhere else (you know, like dual 15mm 3M belts). I don't want the weakest link to be all the bearings, as that's what moves the 3 main axes.

I also didn't know that the seal gap wasn't supposed to be so large. To adress the points about future availability and get something that probably runs better, I found these 608ZZ's on AliExpress.

No idea about quality, but ZZ bearings allegedly run smoother than 2RS as the rubber seal isn't in contact with the wheels. The ZZ's probably would have a better seal that the RSs I have now. I'm thinking of using the ZZ's for the sliders, and some of the 200 RS bearings will be used in the sliders to squish the double belts together.