I used an 8.1 sporadically for about a year. Had zero problems with the marker or mags, but I was running with five mags, and it was noticeably heavy. I definitely got a good three mags off of a cart.
A while back, out of curiosity, I traded my 8.1 for a tpx. I was blown away by how much lighter the mags are! I immediately made a ten mag rig for myself. After a short time, I settled on nine mags total, eight in inches and one in the gun. I can honestly say the entire rig is barely noticeable in weight. Additionally, the more "uniform" shape of the tpx mags makes them easier to use in a wider range of pouches, IMO.
-The tpx itself is lighter, but I don't really think the weights of the pistols themselves make a difference since they will be used as primaries. Truth be told, I sorta prefer the 8.1 in form and weight, but not enough to deal with the mags.
- I too was worried about co2 changes with the tpx. My worried were unfounded. Changing carts is incredibly easy.
- one other are where the 8.1 has the advantage is reloading mags in the field. The Tiberius mag detects are much easier to deal with
Overall, when I switched to the tpx I went from using a pistol about 30% of the time to using one over 75% of the time....it's that much more enjoyable. And it's almost all due to the reduced weight of the rig.
Dye DM12, CCM T2, Tippmann TPX. my feedback