I know I've said this before, but I'm very impressed with albermarlesounds (Ricardo)... you generally receive viable seeds, which is a good start... he only lists seeds that are very fresh.
My experience so far is that the lowlanders I've bought from him have turned out to be exactly as described. The highlanders are much slower, so I don't know what they will turn out to be....
And even then, Ricardo is only as good as the people who go out into the wilds to collect for him... I've bought N.naga from him 3 times, and I've got seedlings that are quite clearly 3 different things.
I've tried N.jamban from him 3 times (3 different collections), and never got germination at all.
Similarly, singalana I've tried 3 times over the last few months, and each time got only one or two seedlings.
From one pod of bongso last year, I got 3 seedlings that are radically different from each other.
From a pod of ramispina, I've got a nice uniform batch of 6 month-old seedlings, all about 1cm in diameter, all except one seedling from the same pod which was smothering its fellows and is now about 5cm across.
So really, I'm just agreeing with what everyone else has said on this thread. Albermarle sounds is the one and only reliable ebay seller; when you buy seeds, it's a shot in the dark and you might get nothing at all, exactly what you expect, or a mixed bunch of the species and hybrids even from a single pod.
My feeling is that buying a pod of seeds is a bit of a gamble, but it's a much more exciting gamble than a lottery ticket.