Experience with the Montbell Breeze Dry-tech bivy?

Ryan, I just recently started using the dry-tech bivy and I think it is amazing. I have posted here several times asking for other peoples thoughts on the thing because it really goes against the accepted norm that a waterproof breathable bivy will result in excessive condensation.

I have used it in temps ranging from 22 degrees to 58 degrees in Eastern Mountains. In these conditions under my MSR Hubba my rain fly in completely soaked on the inside. But in the mont-bell I have yet to find any moisture inside. I'm convinced that at least for me the thing does indeed allow the moisture to escape.

It is extremely reasonable in price ($100.00) and I can vouch that the weight is as stated (mine without stuff sack is 6.3 oz).

I have only used it 4 nights now so I am still experimenting. The only issue is that it is not real roomy. I would think a 4 season bag would be snug in it, but my marmot hydrogen and montbell 90 sleeping pad fit inside just fine. I am 5'9.5 " and weigh 155 lbs.

It also does not have a side zip so you must "worm" in through the opening. I do believe that my bags are a good 10 degrees warmer then rated when inside the bivy. The hydrogen is a 30 degree bag and I was fine sleeping under a tarp with this bivy in 22 degrees without extra insulating layers.

Anyone else with experience using this thing?

Jamie

No experience, but given all the new options out there in the last couple years, it might be time for BPL to do a state-of-the market report on WPB's and an assortment of products made from them… bivies, rain jackets, etc.

I've got one in the long & wide and even that is very lightweight. On the first night I used it, I camped next to a rather large river (nighttime lows were in the 40s) and wetted out the chest area of my sleeping bag by letting some of my breath go down into the bivy. It's hard to keep your mouth and nose completely sticking out of the head hole so internal condensation happened. This was on the start of a 3 day backpacking trip, so it was a bit of a headache to find out what had happened at the time. On the next two nights, I was sure to keep the bivy pulled down below my chest and didn't experience any condensation. I also learned to camp way at the top of ridges rather than down in river valleys so that might have had something to do with it.

I don't have any experience with Goretex or eVENT bivies, but it seems like at the very least someone could cannibalize a Breeze-dry tech bivy and make two breeze-dry tech topped/silnylon bottomed traditional-style bivy sacks.