I think the DPR review of the 55/1.4 is very fair. AFAIC it is correct to describe it as a significant improvement over the FA50/1.4.
The three issues I take with the review is that it suggests that
- there is a QC issue on the basis of three copies (haven't heard about 55/1.4 QC issues as much as I heard about 16-50/2.8 QC issues), and
- that similar problems do not exist with other lenses, and
- that FF/BF is something specific to the 55/1.4.
Regarding 1: Yes, they should not have had such difficulty to get a good copy, but who knows whether their copies all came from the same batch of duds?
Regarding 2: I don't like it at all but I keep reading about lens buyers returning their copies because of decentrering and other issues. This seems to happen with all lens manufacturers.
Regarding 3: I don't get why the reviewer seems to indicate that FF/BF is an uncommon phenomenon. If it were, why would the K20D/K-7 (and other cameras from Can*kon) have an adjustment feature?
Not sure what the chances are for the 55/1.4 price to come down in due course, but in any event I think the DPR recommendation should not have included the "with reservations".