Thanks for the pm, I will reply. I have both fixed and adjustable single sixes and like them both. I think for casual shooting either is fine. I prefer the looks of the fixed sight, but again its a personal issue. The fixed most likely won't shoot as tight as its counterpart but once you know your guns tendencies you can shoot all day and be very satisfied.
I would suggest you own both and just enjoy the options. Hope that helps but again it is a personal taste and accuracy issue.