Thanks X-ray, I went through your extensive 35mm ASPH/Biogon reasoning on other related threads, your opinion is veluable one.
Wel, Nokton isnt' an option due to its size/weight, and I my style doesn't prescibe the necesity of as fast lens as possible to the level of being ready to sacirifice size/weight.
I'd be fine with f/2, probably as fast as 1/4 would certainly suffice by low-light ambitions yet allowing manageable lens sizes.
Now as about Biogon - this one is a serious contender. From what I gather from related discussions, its flare resistance is probably the best out of the bunch, its common optical qualities appear to be non-questioned as well. Size-wise, indeed one appears to be shorter then 'Cron ASPH with hood, but I'd stress the fact that I always use len's dedicated hoods with all my lenses. I do nto consider an option of using Biogon without hood comparative with others with hood, and having hood attached Biogon does appear to be considerably longer then 'Cron. Am I wrong ?
I'd also be glad to see an obvious comparisons side by side of OOF renditions at few wide apertures of Biogon vs. 'Cron ASPH...