I've only used this a couple of times. Nothing wrong with it. Hoodless, zipperless, less insulation and wider fit in upper body (to wear your belay jacket).
Reason for selling: personally I've had bad luck with down (not this particular bag) and on trips where I would potentially use this I pretty much always end up bringing a synthetic bag because I'm a big wimp :-)
Significant differences compared to the Vireo:
1) dry treated down
2) warmer (14+oz down fill vs <10oz)
3) heavier (it's warmer...can't have it all)
Specs are pictured below.
I would say this will fit you well if you are ~6' and slim.
New Vireo is $350. Looking for $300 shipped. This is a better bag and you won't find a comparable one easily (lead time at Nunatak is 2 months and you'll pay a lot more than $300).