Later this week, I will have to install a new pfSense system.
I see that version 1.2.1 is nearing completion?
Is it ok to use it in its current form (no showstopping issues), or should I wait for final release (any ETA?) ?
As every other post on the issue of release dates has said - it'll be released when it's released ;)
As far as whether or not it is suitable for use, only you can really decide - read the forum and see if the problems people are reporting are, for you, showstoppers.