I'm thinking about getting a Rolleiflex, tessar- or planar- type f3.5 lens on a flexible budget.

When shooting wide open, is there a noticeable difference in (from your experience)
1) Center-resolution
2) Bokeh qualities (is one smoother than the other)

I'm thinking about a Rolleiflex MX-EVS or a Rolleiflex 3.5e because I've heard good thinks about both. If I do get one, I'd like it to be overhauled--where's a good place and what's the approximate price?