Biggest mistake, probably buying a fabulous Threshold T-200 power amp used and finding out it didn't mate with ML SL3 electrostats. It was twenty minutes of music and you stopped...had to sell it...still have the SL3s (in home theater now).
As a surprise, the Carver AV-705 multi-channel amp sounded much better than either my brother or I expected and he used it a while on Thiel 2.3s (late 90s). It was a steal, bought used.