I just have to share my view on this matter and of course my opinion will just be one among many - because there not one "true" performance, but just a lot of different ones, I guess, and mostly from very accomplished musicians - so it must be a matter of taste.
I read that one reviewer on Amazon preferred the version by the "Alban Berg Quartet" over this one here by the "Borodin Quartet". I have now - here in my Holidays - have the opportunity to compare them both and I for one disagree. To me the Alban Berg Quartet (ABQ) doesn't sound at all as committed as the Borodin (BQ). It is something that, to me, doesn't take very long time to discover why.
I've just compared the first movement of the "Harpe Quartet" opus 74 and the BQ has a much more lively, engaged and dedicated expression with lots of warmth, dynamics and balance - the last thing is very important... Here the ABQ sounds much more strict, 'hard' and not as musical engaged. A very obvious place to compare is when I first heard the version with ABQ - approximately 4 minutes into the 1st movement there is a passage where we have a slow melody on top, with a very busy and energetic cello/viola accompaniment at the same time - to me this at first didn't make sense - it sounded like they were fighting among each other... Put on the BQ and voila! Here it makes totally sense - so precise and with a great balance where the slow melody stands out and the busy runs forms a beautiful energetic accompanying contrast... To me; this must have been the composers intention. Also another great thing about the BQ is their dynamics - overall it sounds much more musical and 'round' than the ABQ, but when attack and strong playing is required - lo and behold - here is all you need and on top; played with surplus energy never sounding strained.
Well in short - I have heard the two Borodin CD's with Opus 59 and Opus 74 and to me this can't simply get any better - such dedication and such depth is exactly what these masterpieces crave. I can't wait to get my hands on their remaining recordings of Beethoven's string quartets.
And oh, the recording is great too - highly, highly recommended.