I went two times (8 hour drive) , it is huge and has three different interests:
- the show itself: IMO interesting but not great, a lot of marketing people that can or will not answer detailed technical questions. If you are in marketing or buying it is probably a must, if you are an engineer you might find some new components or get some contacts with firms sales people, don't expect 1:1 with other engineers or deep technical discussions, might happen but that is more a fluke. The nicest experience are usually the free dev boards
- the conferences: they cost pretty much money, the ones I followed were very shallow, they talk about projects or market developments but rarely show it all or talk in technical depth about their effort and achievements. Universities are good conferences with new developments and since they are not in an industrial competition they tell more than companies. TIP: if the conferencetalk is over and you talk to the guys 1:1 at the hallway/coffee you sometimes can do very technical discussions and find out the interesting things. So this can be interesting if the talks are in the field of your interest.
Overall nice to go if the company is willing to pay for it, but if you have to pay for it yourself incl. hotels etc. I would skip it.
- the classes: also can be very interesting to do a 1 day class to get a feel of a subject you know too little about.