The Maestro Vibrola is FANTASTIC, ...IF you LOVE wang bars. I do, I just cut a whole in my new Firebird to add one! Don't throw things at me please, it's only an FR-53.
The Maestro (curved metal blade) is unique and wonderful, but only for the slight de-tune. Think Wishbone ash, Moody Blues, etc. It will NOT dive Bomb! If you try, it won't really do it, and may cause SLIGHT tuning issues. If you take a light touch approach to it, it is great. They were somewhat unpopular, I think largely because of novices not knowing what they were doing (no offense to any one here who had a bad experience with one). Hard core Stop Tail piece guys HATE this trem above all others. VERY IMPORTANT, if your nut "catches" at all, tuning is an issue with any trem, even if you have locking tuners. Lubricating the nut is worthwhile on any guitar...as has been discussed recently on this forum.
On the topic of locking tuners, I've had Sperzals, and liked them. However, if you only do a single winding when putting strings on ANY tuners, the instrument will tune better. Bending after all does something not that different from a trem. I know people who put 1/2 dozen windings on the tuner, but I feel that just gives more opprotunity for the windings to loosen when playing hard, and then return to a different, out of tune spot. I play hard, but am gentle with the trem, maybe an odd approach, but I have excellent tuning consistancy.
As for the Les Trem on Ebay. I have one, now in a drawer. The major problem I had with it was related to the arm. These currently available have an arm mod, and are certainly better. Additionally, this seller seems knowledgeable about how to maximize them. The price is low as well, compared with what they generally cost. Worth a try if you really want to detune while playing. They sound/behave much like a Bigsby.
Sorry if I added to this thread getting off topic.
*I REALLY want this SG, but am waiting to buy another Les Paul first, I won't bid against you, but it is VERY VERY tempting. Hopefully the price won't enflate at the last minute.