I will provide a third. My Reo Grand with RM2 will leak if I don't use the little o-ring. I lose the o-rings sometimes because I wash the RM2 without thinking about it and rinse the o-ring down the drain. I re-assemble sans o-ring and go about my day. It doesn't take long to learn of my mistake by the juice all over the top of the mod.
Now I will say I put the air-hole in the same place every time so without the o-ring the RM2 isnt' screwed all the way down, and my guess is that contributes. I've never tried to see if it leaks without the o-ring and screwed down tight but those air paths cut into the top of the connector look like they would allow juice out to me. I don't think about it much because it works fine with the o-ring. I just consider that part of the RM2.
Yeah, I mostly don't use o-ring for very same reason.... I forget and they run off when I take RM2 off. It doesn't leak that badly and I usually have something to dab even if it's my grub work clothes or apron.
Feisty Alice
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