Talk me out of trying this.
The RIDGID Sub-Compact cordless 3-inch multi-material saw is cheap. Way cheaper that any cordless angle die grinders. At least for the moment in Canada, it's cheaper than other cordless multi-material saws too.
When I look it up on parts websites, it seems to have an M6 thread on the arbor - which is interesting, because while Roloc disc holders have 1/4" shafts, they are available with M6 threads on the part that screws into the disc holder. Could an enterprising person not just screw an M6 set screw into the saw and connect the two?

The Ridgid's max no-load speed is 19,000 rpm, which is compatible with some Roloc discs. It also has a variable-speed trigger, unlike many other 3" cut-off tools. So presumably you could feather it down to avoid obliterating discs with lower speed limits.
The worse thing I can foresee happening is if the set screw broke off in the tool arbor. But if you used a high-grade fastener, swapped it occasionally and didn't intentionally abuse it... M6 seems plenty strong. If you intentionally used a fastener that didn't bottom out in the tool, that might also reduce the risk of not being about to get a broken one out.
TTC's tests suggest the Ridigid is pretty powerful too. Even if it turns out it can't keep up with a 3" roloc, what about a 2"?
I realize cordless angle die grinders exist. The only reason to try this is the cost. It looks like they start at ~$300 in Canada as bare tools. This Ridgid saw is $139. And then you also have a saw.
The RIDGID Sub-Compact cordless 3-inch multi-material saw is cheap. Way cheaper that any cordless angle die grinders. At least for the moment in Canada, it's cheaper than other cordless multi-material saws too.
When I look it up on parts websites, it seems to have an M6 thread on the arbor - which is interesting, because while Roloc disc holders have 1/4" shafts, they are available with M6 threads on the part that screws into the disc holder. Could an enterprising person not just screw an M6 set screw into the saw and connect the two?

The Ridgid's max no-load speed is 19,000 rpm, which is compatible with some Roloc discs. It also has a variable-speed trigger, unlike many other 3" cut-off tools. So presumably you could feather it down to avoid obliterating discs with lower speed limits.
The worse thing I can foresee happening is if the set screw broke off in the tool arbor. But if you used a high-grade fastener, swapped it occasionally and didn't intentionally abuse it... M6 seems plenty strong. If you intentionally used a fastener that didn't bottom out in the tool, that might also reduce the risk of not being about to get a broken one out.
TTC's tests suggest the Ridigid is pretty powerful too. Even if it turns out it can't keep up with a 3" roloc, what about a 2"?
I realize cordless angle die grinders exist. The only reason to try this is the cost. It looks like they start at ~$300 in Canada as bare tools. This Ridgid saw is $139. And then you also have a saw.