Large scale meets are indeed useless for any meaningful impressions and only a smaller setting or having something on loan will yield anything of substance. It's also interesting how people are "tricked" at the larger meets with higher volume levels, choice of music etc.
Buying used Stax sets does carry risks but if the sets look to be in good condition then they will work perfectly. I've bought enough to know this isn't a perfect rule but it's true enough. I still can't help myself when I see some truly busted up Stax stuff to try and bring it back to life. Let's just say there is a reason why I have a large stock of single drivers...
I've done plenty of that but their voicing just irks me a bit. They are just a bit hyper real at times, like a TV with all the post processing turned on.