Zeiss 35mm lens question for use on my ZF

I'm looking at getting either the older Zeiss 35mm 1.4 zf.2 or the Zeiss 35mm f2 Milvus. I have a ZF and primary using the older Zeiss/Contax primes. I love them for travel and that older "look" they have. I would like a 35 with electrical contacts that's a little brighter. Possibly down the road pick up a 50 1.4. Besides the obvious advantages of the F1.4 being brighter and the F2 having better weather sealing. I'm curious for those who have owned or used either what were your impressions? What did you prefer and why? I would like a better low light lens, but I live in Colorado so the weather sealing would be nice for hiking.