Are new Mark Levinson Preamps better than old?

I doubt you would be able to tell any of them apart in a blind level-matched listening test.

If you want a better preamp than the ML380 and want to stay in the ML family, don't look forward, look backwards to the ML26S. 

No direct experience here, but recall reading of some having reliability issues with more current ML gear. Hopefully others will chime in. 

Thank you for your comments.  I know Levinson gear was legendary in the 1980s and 1990s, and I have been lucky with my two units from the 1990s: the ML 380 preamp I mentioned and my ML 332 power amp, each of which I have had repaired only once.  As I said, I am thinking of upgrading at least the preamp, but the two issues that I need information on are: do new Levinson products sound noticeably better, and are they as reliable?  I would have thought that 27 years of technological progress would offer better sound, but so far it sounds like it may not be a great idea.  If anyone else can provide more information, I would appreciate it.  I don't want to part with that kind of money and have no noticeable improvement.

I was using a 380S for nearly 20 years with great satisfaction.  I recently replaced it with a Primaluna Evo 400 which I find superior in the qualities of sound stage and musicality.  The only function I miss on the 380S is the ability to fine tune volume.  In this area it is unmatched.