I have listened to the ARC VT-100 Mk2, the VAC PA90's and Renaissance 30/30's, numerous Cary models including the 805's, the 15 watt integrated and the Rocket 88, have heard the Graff OTL amps but not the one you mention, have also heard BAT VK-60's but not in a familiar system and own the ZH270.
All the above amps are excellent products in one way or another. The Cary's are rich with great staging but lacking more at the frequency extremes as you would expect from a single ended design. The ARC is an excellent amp with top to bottom resolution and wonderful bloom with excellent detail. The VAC 30/30 has a great midrange and is totally unfatiguing. The Graff OTL was in an Infinity based system and what can you say, it has that pristine clarity and tube presence that is only obtainable from OTL designs. The BAT I can't comment on with much credibility to its sonic character because it was in a unfamiliar system which was very involving.
There is no clear cut answer because it isn't clear what your priorities are. The Berning will offer much of what the OTL amps do since it doesn't have a transformer, clarity top to bottom unmatched by any of the above amps. Some of the others would be darker sounding (BAT and Cary) by contrast. I can't say first hand concering the BAT because I haven't listened enough but I have spoken to many with much experience with this amp and this seems to be the general concensus. Not to say this is a bad thing. Conrad Johnson also falls into this camp but it is a sound preferable to some.
All said and done I personally believe that OTL type amplifiers are closer to real because they don't mask anything. Best thing to do is listen and compare to find out what you might prefer. The Berning with several mods holds up to anything I have heard tube or ss. It is an extraordinary amplifier stock and reference calipre with the mods.
Pluses - Excellent track record for reliability, low heat, long lasting outputs (20 years or so), 2 inputs and volume control for direct connection to line level sources. Negatives - It ain't no beauty queen and won't give you a hernia when you lift it (only 10 lbs). Ahhh but we audiophiles sometimes like to make it hard on ourselves, no?