Hi, Lev. One of the two, the SL3 I beleive, is more difficult to drive. I happened to audition the two comparatively at a dealer's -- pls note, not at home. I listened to orchestral music ("Thus Spake Zarathustra", audiophile recording, what else/ Vivaldi, String Concerti / P Floyd "The Wall" on LP), cabling was Nordost 4fil / spm ref, amplification: Symphonic Line Kraftquelle pre / Kraft 250 classA power.
With this set-up (again, at the dealer's) the SL3 sounded closer to what I think is natural sound -- so, better (esp. for classical). As to a *big* difference, a jaw-dropping, etc, difference... I missed it, with all due respect to yr dealer.
But then, you have ML electronics (right?). Maybe those will better reveal the difference??
Cheers!
