this could be true if no one owning both could/would say they preferred the zavvi one(which is supposed for you to be far "worse" than the blufans one)but it can't be, since some like paul own both and say they'll prefer the zavvi one..
there are basically 3important things(most important ones for the steel itself) to a steel:
the type of
Finish(shining effect etc or not, glossy or matte finish etc,colors,resolution etc)
the front art choice
the back art choice
most people seem to rather the BF front art, but what about the back..
personally i've always loved and rathered this back art over the BF one
in itself(i know some are thrilled by steelbooks that have front and back maching even though the back "is"/feels a lot empty even for them)i 'm pretty sure most will much more rather the zavvi back over the blufans one with just the sky etc
plus the same can be said to those who have the blufans edition(that they can't criticize what they own)
the finish is less good on the blufans (blufans zero finish at best, zavvi glossy finish) and that's an important point for most of collectors( and by the way for me it has a pretty dull look depending on the light and angle when there's not light on it for instance)
the rest(art) is (at least/best)more or less a matter of /subjectivity..
oh and it's not because i don't have the blufans that i say all these, cause i have it and will sell it