There are differences in the individual chips, some will naturally run hotter than others...in addition, mounting the waterblocks is not going to be identical on all chips....so there are a lot of variables that could affect temps...as long as they are in a safe range you should not have anything to worry about.
@jjiimm_64...well, due to the outlet being limited to 20A...wouldn't it "go" before the wires (unless there is a short circuit in the wiring or something...), which should handle 20A just fine.
When I say 'running a 220' I mean run 10 gauge wire from a 30 amp breaker to a 30 amp twistlock plug.. get a proper server strip with c13 cables and you will be able to run 3 terras and be more efficient and safe.