Advice on lens - wide(r) prime

This topic has been discussed here a little already.

I shot with my 50/1.4 about 80% of the time, and have found I am often wanting something just a little wider, but still nice and fast. I have narrowed my selection to the following and wondered what people thought.

Pentax FA 35mm F2
Pro - SMC, small size, good lens
Con - Seems I can only get it on eBay

Sigma 28mm F1.8
Pro - tiny bit faster, available not on eBay, cheaper, pseudo macro
Con - some concerns about front focus (easily fixed on K7)

at an outside

Sigma 30mm f1.4
Pro - Faster

Con - some concerns about image quality from what I have read, but happy to be told otherwise.

Any ideas?

Cheers, Tim.
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