Thanks to everybody, especially the ones that made it possible to receive these plants. I have more pics to post, just have to get them properly labeled and find good pics to share.
Desertkoigal, the answer actually is "it's impossible to tell". They change so much in appearance over time and with different growing conditions...
Now, if you knew you were dealing with a limited pool of two or three semps AND you knew what those had to be, you could probably sort them out using other pics and the db. That is why labeling is so important.
