Don't buy anything, trust me. Treat the expos are a place where you go and open your eyes so you can gather info and then do actual research on the stuff you need to buy.

Expos is a place full of bullshit and irrelevant ideas most of the time. There can be a few hidden gems where some are actually genuine in giving you a good deal, but for the most part - you can always get something better outside. Also avoid those who always say "this is fair price only, once you miss it, you miss it forever!". Those kind of bullshitters you'll see again in the next expo a few weeks later lol.

So yeah once again, don't buy anything.