I think it would be fine and here is why. I was finishing a part built loco for a young bloke. Rushing to get to the exciting testing on air, I merely pinched the piston rod with an M3 grub screw through the side of the crosshead. The rod was a good close sliding fit done by the original builder, whose workmanship was a pleasure to take over (rarely the case!). This was forgotten as the engine was finished. It has been running for years, pulling heavy loads. Still just the little grub screw. So a roll pin would be luxury! There is theory and there is practice.

Verify that you have decent quality roll pins. I'm underwhelmed by the ability of single split ones to stay properly round and secure.

Especially the modern "affordable" box sets. My almost affordable box set was got many years ago and said to be of engineering quality but I've had trouble with pins crushing slightly out of round and loosening under quite moderate loads. Some of the "can you fix it" jobs have roll pins in truly horrible condition. Apparently factory fit too.

It appears that it should be possible to re-use them after suitable inspection but I have my doubts.

Spirol types seem much better performers and probably worth the extra cost. Its what I shall buy if I ever run out.

Clive

Subjectively, taper pins seem more difficult to remove (particularly if struck from the big end!).

A possible advantage of the roll pin may be that it is easier to arrange it not to project at either end of its hole.

I have no doubt roll pins are heat-treated in some way but are they really hardened?