Mcfarland AR-15 Bolt Gas Ring - Any experiences?

[Stratocaster1422]

http://www.brownells.com/.aspx/pid=18722/Product/AR_15_MCFARLAND_trade__BOLT_GAS_RING

I bent a gas ring cleaning the bolt on my AR-15 the other day, so I went over to First Defense to buy a few new ones. Well they had these one piecers on the rack, so I figured why not. Didn't really have time to ask Dennis his opinion, so I figured I'd just ask here.

So anybody use them? Do they suck? Are they good to go? Do they multiply when wet and shouldn't feed them after midnight?

 

[Remsport Mfg]

I have used them in the past and they work fine. There is no advantage over the standard rings except you don't have to make sure the ring gaps are staggered. As far as better seal that is just sake oil.