Threshold s1000

I bought these 2 monoblocks a few years ago and spent quite a bit of money updating them to better components and putting in balanced input sockets. This was quite easy I am told, due to the very open architecture and fundamentally solid design. I like them very much and I was recently demonstrating them to a potential buyer, versus  his classe 350 monoblocks, and the thresholds were in another (better) league entirely.
I cannot find any internet information about them and I am inclined to keep them in spite of 2 separate offers from Italy of €4,500. I am reluctant to send to Italy because of potential damage and or disappearance of the 2 heavy boxes to such a  notorious country for causing problems. In my system they are up against Bryston 7b3s (or Bryston 4Bsst2 in my second system) so they need to punch a bit of weight. Just wondering if anyone knows of these rare items and what I might expect moneywise if I ventured to sell as I have too many amps. Something has to give. I know people will say listen and make up your mind, but they are quite different to the Brystons so it all depends on mood and synergy. I could argue for both in their own way, so  I am wavering all over the place
They are part of the Stasis group that Nelson designed, all are pretty similar save for the power supply grows and the output transistors increase as you go up the ladder. from the 150 up to yours, here is the circuit that applies to all of them, except for the additions as you go up in models. As for the 4.5euro offer, that seems good to me as that’s $10k Australian, get him to organise shipping, then it’s on his head. I think you would find better amps today that use BJT outputs like this does, as they are my choice of output device as well.

Cheers George

Hi, I was curious about these amps. May I ask?:

What is the input sensitivity for full power output with these amps?

I've read on the back of Threshold amps that they should only be used with loads over 4 Ohms. Is that the same with these? If not, what is the power output into 2 Ohms with these amps?

Are they now true balanced amps of just have XLR inputs?

If they were the same as the others in the S series they were all normal sensitivity around 27db gain, my passive pre drove them no problems with a 2v source, and there was plenty left on the volume control. 

Cheers George