I have both the 35mm and 28mm in 2.8, excellent lenses, always seems a shame to put a big lens on the OM1. Incidentally, I much prefer the 50mm 1.8 to the 1.4 in Zuikos, probably the only brand where this is the case.
I agree on the lens size and the OM-1. Most of the OMZ primes balance well with the body. The small wides, with the flat barre, give a compact look to the camera.
I've read around that the 1.4 is a bit soft wide open, specially the early models. There's a "Unscientific" comparison between the 1.4s and 1.8s in a blog (om experience). The 1.8 MiJ seems to be the best of the 50's wide open. What I don't like of this lens is the harsh bokeh that often appears on longer focusing distances in backgrounds (3m to infinite).
Oh, and this got me intriguing for a while? The 1.8 MiJ is Multicoated? Mine has reflections of lots of colors, and it's hard to identify clearly. I even think that some elements are SC and some others are MC.
I want march to arrive and have some holidays, it's been quite a while since I haven't shot anything. Must end that roll of KR64. Inactive time gets me into tech stuff.