Has any had experiecne with the MF 550k superchar?

I should have expressed myself more clearly. The reviewer found that the inherent sonic characteristics of the 550 (cold, hard, compressed sound stage, etc. etc.) did not basically change when used as an amp or as a supercharger; they were more pronounced when it was used as an amp, and mitigated somewhat by the interaction with the positive sonic features of the Aleph. The Aleph is one of the more of the more "tubey" ss amps out there, but--yes--certainly isn't an SET.

It's been almost a year now. Has anybody used the 550K as a supercharger? Were the results as advertised by the vendor?

Well sorry for the late respond,I did have the sc MF 550.
I went to Music Direct to pick them up.I have been thinking
if indeed they are the answer for my Andra I who needs a
lot of power to get the best out of them.Auidiooracle you
are right,if you know how to use them,they will give you
the best and they will shine.I myself Iam wondering if it
will change the sonic of my VIVA tube amp,the answer is no.
I have them for 8 months now,I have been enoying my Andra
since I got the 550, the bass,the palpability,the transient
is no comparison without the 550.The secret is good power
cables,they like the model 11 costum power cord,then use
good speaker cable,replace the one that come with the amp.
I think they are also very good amp.You can try them,and
hear it for yourself with your own system.thank Bon

Twoleftears,the reviewer findings did not exist in my system,maybe it was a system mismatch.I like Aleph amp
as well.