That panel pc should work fine. One reason you get it at that price as a panel PC is the CPU is 6th generation. I should think that even a 6th gen i5 would be plenty enough for Pac Display. If you were looking at the more recent 8th-10th gen stuff, i3 is plenty fast for pac display. I have never used the TWAP screens before, but they are probably fine. Touch windows primarily sells to POS market which generally is pretty reliable stuff. You’ll like the PCAP touch, its generally very fast. Personally, I like using the NUCs because for that price, you can get an NUC10i7. That’s a 6 core processor and an i7.
Insofar as PCAP screen go, the ELO has a glass screen right to the edge, which means I use a rubber sealant/adhesive (FLEX SEAL) to essentially glue the screen directly to the inside surface of the panel door, no screws needed, and 100% waterproof. As far as the door cutout edge, if you have a laser cutting outfit available, that makes an absolute perfect edge which needs no additional trim work, otherwise I use automotive trim to finish the edge if I cut it manually.
With regard to the size project you are doing, R1 is way sufficient and if properly programmed, is a screamer. The beauty of the R1 is simplicity with all the power you need and allows even lower point counts of (down to 1 ch analog or 4 ch discreet) while at the same time is capable of loading a 16 channel rack with 32 channel modules and running those like it is idling. It can still do IIOT but not like Epic. If you find that the speed is lacking, you’re either trying to do high speed motion control, doing something wrong, or you’re trying to run 1000+ IO.