Long post warning!
I'm preparing my kit for a Wonderland Trail through hike this summer (end of August) and the JMT the year following. I'm leaning towards a mid sans bivy in lieu of a tarp/bivy as I could potentially find myself in a week-long torrential downpour on the Wonderland. I hope that the timing of my trip will greatly reduce the chance of this happening.
I'm not interested in an integrated bug net regardless of whatever shelter I end up with. If I get a mid, then I'll cover up and sleep with a head net. If I migrate back to a bivy/tarp then I'll purchase my bivy accordingly.
I've found an abundance of information on BPL relating to the MLD Duomid but minimal reviews relating to the Black Diamond Beta Light. I've considered the Solo Plus w/ Beak w/o bug net as well for the weight savings but I'm leaning heavily towards the MLD Duo and BDBL for their bomber reputation, reputed performance in wind and snow, and lower cost.
General observations of dimensions; I haven't seen either shelter in real life:
MLD Duo is rectangular shaped vs BDBL is unevenly hexagon shaped and longer roof which appears to allow for a steeper pitch at the foot and head.
MLD Duo is 8" longer but seems to be a shallower pitch head to foot so not sure if this really adds/reduces/or is equal in usable space length-wise.
BDBL is 1' wider at its widest point but 16" narrower at the head and foot.
BDBL uses two poles in the center while MLD uses two poles (with extenders?) on the sides. Perceived greater flexibility to sleep diagonally when solo in the MLD but will face similar restrictions when with camping partner. It appears that BDBL may be an easier set up and doesn't require pole extenders.
Advertised weight and price comparison close enough to be negligible for me.
I've doubled my efforts to buy American since the recession. I assume BDBL is made overseas so +1 for MLD (relax tenderhearted people I'm not xenophobic.) If all things were equal I would buy American but there appear to be nuances to both shelters which would make them perform differently.
I'm 6'3" and broad shouldered. I occasionally will have a camping partner or one of my kids with me. I'm currently building a pulk sled and want to do more camping in the winter (based in Washington State.) I like having my gear in the shelter with me. If I take on the weight penalty of a Mid in lieu of a traditional tarp, I will forgo a bivy to mitigate the weight penalty. I'll use BD carbon corks as my poles.
Please let me know if I've misunderstood any of the characteristics of these two shelters. Any input is appreciated.