Contrast/compare 50W tube amps

I'd have to disagree with the assessment made about the Dehavilland GM70.I run the Alon Lotus Sigs,open baffle,2001 model.They give tight quality bass,midrange in the you are there,and a very extended top end,the choice of tubes and interconnects can change the sound to either side of neutral,and will also dictate how much warmth.I play classic rock,jazz,vocals and I must say i'm very happy with the sound in MY SYSTEM..YMMV

of your list, quicksilvers are the ones with the magic. check cj, mac, arc, vac, and music reference as well, if a tube amp or amps is your destination.

Have you considered the AES Sixpac amps? They are made by Cary, are very nice, and IMO are a bargain. For a few dollars more you can have Cary upgrade the speaker binding posts, add a balanced input, and install upgraded caps. You can change the KT-88 tubes for KT-66's if you like a warmer sound. They are 50wpc with KT-88 tubes. Here are a couple of reviews:

http://www.positive-feedback.com/Issue6/sixpac.htm
http://www.soundstage.com/revequip/aes_sixpacs.htm

BTW I have no affiliation with Cary or AES; I just really like the amps.

I have some issues with the Cary gear,would rather consider the VAC Renaissanceor PHI series.
Same for the ARC and CJ,both have an identifiable signature on the music.Sorry -don't wish to offend!
Thanks for the observations.The GM-70 and Quickies are moving to the Front-of-the-Pack.
No further comment on the Atma-Shere/OTL route??

Many would be quite happy with the DeHavillands. But I could not get them to drive with the energy of the Quickies.