Serious questions deserve a serious reply:
I am curious how you like your Maven B.3 6x30's. Are they as comfortable to use as a full size binocular like an 8x42 because of the 5mm exit pupil?
Yes, I think they are. Not just because of the exit pupil size, though that
is important, but also because of the decent eye relief. I find them very comfortable in use and probably my most comfortable bins when used with glasses. Also understand, though, that I mostly use them for the reasons described here:
http://www.birdforum.net/showthread.php?t=329552
Are they bright in low light
I'd say "not especially" - but for my use, they're really not supposed to be. When the light is low enough that I can't make things out through my 6x30s there's little enough light to take a photo.
and do they have enough magnification to see detail on birds?
Generally, enough detail for an ID. But for my use (see above) that isn't critical or even especially important. What I really need is the wide FOV to help me chase the birds to get close enough for a photo. And the B.3 6x30s certainly have that. Excellently so.
Also, what do you like about your Zeiss 8x32 FL's over the Tract Torics's 8x42.
Well, the major thing I like about my 8x32s over my Toric 8x42s (and many other bins) is their size and weight. Absent those advantages I should never have bought them. But I don't think that was your question.
What I do like about the view - size etc. notwithstanding - is just how "clean" it is. Truly minimal CA, very little flare - whether direct or veiling - high acuity and so forth. The only bins I have any time with that I'd rate as better on a "view over anything else" basis are my 10x56 FLs. That doesn't mean that some other bin from Zeiss (see: HT or SF) or Swarovski or Leica or Nikon might not be better (I haven't spent the time needed to know, just looked through them in stores) - and I've no reason to believe that others couldn't do as well or better either. I just haven't personally seen that. I do know, by direct comparison, that as good as my Tract Toric 8x42s are (they're well good enough for me), I can see that my 8x32 FLs have an optical advantage. My 10x56 FLs have an even bigger advantage - but, as the lass said, "well, they would, wouldn't they". Nothing exceeds like excess, and those 56mm objectives have a big bunch of (obviously high-grade) optical real-estate over any x32 or x42 alternatives. (Note: at my age, I doubt a larger than 5.6mm exit pupil would do me much good in any kind of light.)
I have had the FL's and they are excellent binoculars but I would think the Tract's would be a little more comfortable with easier eye placement and would be a little brighter with the bigger 5mm exit pupil.
You are correct. But I'd take the size and weight advantages of my 8x32 FLs first and foremost (they matter to me rather a lot) and take their optical advantages (see above) as an added bonus (while taking the $$$$$ involved as a substantial disadvantage). And you might note I said "my FLs" - which includes my 10x56 FLs - and those have a larger exit pupil than my Torics, give (marginally) more comfortable eye placement and are a fair bit brighter - while being way, way, way, to big and non-portable for most of my uses. They also match or exceed the advantages I described for my 8x32 FLs. They're just too inconvenient to carry around, much. But where I do use them (more often than not, tripod-mounted from my balcony) they give me a truly excellent view. I've not seen better - and if there is a better view, through a set of bins I've not seen, well, forgive me if I doubt it's better by much.
...Mike