Subjectively speaking and with deep respect for every ones opinion on this thread i say an amplifier with 2 ohm rating may be an amplifier which has a high power rating. To get the best sound or unleash the full potential of Martin Logans a powerful amplifier is necessary. Especially for ML models which have estimated 1 ohm resistance at 20 khz frequency.
I have owned two integrated amplifiers both with maximum 4 ohm rating. The sound subjectively speaking from the MOSFET Sony was very good and for the UHCMOS Denon was between good and very good. A point to keep in mind is that i had the Sony when my CLS were recently acquired and the Denon after some time. One reason for the good sound with low power amplifiers is that the resistance of CLS is 1.6 ohm at 20 Khz. The CLX at high frequencies has a resistance of 0.6 ohms and needs very powerful amplifiers to sound its best.
To conclude, the lower the electrostatic panel resistance response at high frequencies the more powerful, more expensive and thus better sounding, higher quality with premium audiophile grade parts, amplifier required. Subjectively speaking and i may be mistaken that for top octave response from a low resistance electrostatic panel, that gives the aural impression of air, a 1 or 2 ohm rating amplifiier is required.