NAT se2se

I'm about to pull the proverbial trigger on buying a pair of these directly from Dejan in Serbia.  Can anyone offer comparative experience bet. the older 211 version and the recent GM70 version?  At least from descrips, it seems other design changes have been implemented in addition to output tubes.  
I know you had the opportunity to hear this amplifier  in your own system. What impressed you about this amplifier compared to the others you've heard in  your home? I've hear nothing but good things regarding NAT Audio.
Hello Charles,  Actually, have not yet had the opportunity to hear in my system.  I have a colleague (lives a few hrs away) who will be teaching overseas for a couple months, at which time I'll be babysitting his!  He has the older version w/ the 211 output tubes.  In his system, the se2se aid in a beautifully clear presentation.  Very authoritative, solid low frequencies w/o being overwhelming.  I just have no idea what, if any, sonic changes have taken place with the newer version.    
Get touch with Gon member Spiritofmusic. He has these amplifiers and  can offer I believe some meaningful insight. He really loves this amplifier. 
Thank you, Charles.  I'd read a few of his posts concerning the se2se, and in fact emailed an inquiry to him yesterday.  Will look forward to his thoughts when he has a moment.