Do all 6550 based tube amps sound the same?

I am looking to add a tube amp to my system. Both of the amps I am interested in, Conrad Johnson Premier 12 and Audio Research VT100 MK 11 or 111 use the 6550 output tube. In your experience do they all (6550 tubes) share a similar sonic signature? Thanks for your help.
No they don't sound the same. I like AR sound much better than CJ. I would like and old HK Citation even better!
I'll second Elevick's statement, they don't sound the same. Even 6550 tubes themselves from different manufacturers have different sonics. Plus, any amp utilizing 6550's in the output stage probably has tubes in the input and driver stages as well - further factors in sonic signature. There are SO many variables in the sonics of tube amps...
The CJ premier twelves have a naturally warmer, more easy going sound than ARC amps and more than most amps actually. My choice would depend on other gear in the system.
The fellow asked a good question, the truth of the matter is, yes most 6550 tube based amps share a common sonic signature. Do they sound the same, no, as stated in other posts different input and driver tubes as well as brands will affect the sound. Viridian, your answer is sarcastic and adds nothing to the tread. By the way, I have built tube amps since the 1960s and have some experience in this matter
Just curious, what is the formal defenition of "sonic signature", as I might not be using is properly. Thanks :-)

ps - notice how Viridian pulled his post?
Yes, you guys are right. I pulled it because it was meant as a jibe at the "objectivists"(all amps sound the same school), there's a misnomer for you, and, after rereading it, I was concerned that it would be interpreted as sarcasm directed at the original poster. Clearly, my fears were warrented. I regret that I am not always the clearest communicator.
Most amps sound different. Though it is subtle in similar dedigned tube amps with same tubes. I own an arc with 6550's and the P12's which have Kt-90s they both sound great. I would say that the CJ is a little more romantic, its hard to explain. While both amps have great soundstage and defination the CJ is a little more softer , mellower sounding. You can also check with Kevin @ in regard to which tubes will suit your music style. Both amps are among the best available. You will probably love either one. BTW make some room they are both pretty big !