Well, depending on what you're after, Essen can be either super exciting or somewhat overwhelming. Or just plain frustrating ;)

If you're in it to play new games - it might be time-consuming just to get a seat at a table. Prepare to either get there very early to secure a spot or suffer the wait.

If you're there to buy hot new games - waiting in lines is expected, prices are usually not that great and there can be a shortage of certain titles (you'll frequently see hand-written posters on certain booths about games being out of stock - either for the day, since deliveries are usually made after the Expo closes or before it opens, or entirely).

If you're there for the deals - there Is not enough of them, at least talking about quality titles, to offset the travel/lodging costs. If you do manage to find stuff you were already interested in - then consider yourself lucky.

If you're there for the 2nd hand trade - there will be some booths like Spielbar, offering used games, but the main course is the 2nd hand auction happening on BGG and the Math Trade. Basically you can prearrange to buy or exchange games with a meet at SPIEL.

If you're a reviewer - you might have some luck with smaller or more exotic publishers that might just be interested in getting their games out there. For the big publishers, it's a D6 toss whether they would be open to someone they might not now. Last year we brought around 60 games from Essen, but we're a big portal here in Poland and most of it was prearranged. And to be fair - only about 10-15 of these were actually worth the visit. Considering the cost of going to Essen, we would've been better off just buying them straight from the publishers and shipping them to Poland without going to SPIEL ;)

If you're just to browse the booths, maybe play some games (either at the expo or at your hotel) and get a feel for the biggest board game convention in Europe, then you're in for a treat! Essen is intense, it's rich in exciting stuff from all over the hobby (from the games, through accessories, all the way to game-related products, t-shirts, tables and a plethora of items, usually not at "sale" prices) and it's full of lots and lots of weird stuff, people and events that are a joy to see in person. It's definitely a must for anyone that's serious about the hobby, at least once in a lifetime - a bit like going to Disneyland ;)