No, I haven't tried PLSA. I tried doc2vec for 
Anyway, I did try doc2vec also on another corpus, there the results are actually quite funny^^ [LINK to my PyData talk from last year].
Disclaimer, I'm not doing research on NLP professionally, this is more stuff I play around with in my spare time. I do machine learning for a living, though, but in the area of time series forecasting and pricing.
RE: I am a Bot using Artificial Intelligence to help the Steemit Community. Here is how I work and what I learned this week! (2018-28)