Dynaco owners please comment

I recently bought a Dynaco 120c and wondered is there any differences in the models. I have noticed some with the A series on them.Also I'am very impressed by the quality of these vintage amps and wondered why I have spent more money and not gotten the sound quality of this 60 wpc amplifier.These little amps are not embarassed by SS amps in the 3K to 4K range IMO.Since I have owned a few in this range I think it's a fair judgment.Also what do you guys use to keep the chrome on these amps looking good ? I think I'am hooked and will have to have the whole dynaco setup.Anybody looking for a SS or tube amp owes it to themselves to try one of the dynaco models out before spending more! David Hafler rest in peace! Thanks for any and all comments!