I go most years and I think that attendance is falling, sadly. This year the flea market was noticeably smaller and most traders were not doing brisk business. So get there while you can because i fear for it's future. One reason for this is that the German revenue men have taken a strong interest in the "professional" traders on the flea market who sell stuff for cash. A couple of the big guys got hit with $60,000 bills for tax (which is based on 20 percent of profits) so it just goes to show how much some of them are making. Another is theft. One of the big traders did not turn up this years because, last year someone stole a days worth of his takings. And there were pick pockets about working in teams. There were warnings about this on the PA and both uniformed and plain clothes cops were about.
One guy had his pocket cut open and his wallet stolen. But for the vast majority of the people attending there were no problems.
Prices on the fleamarket were quite high. This year second hand valve testers were the big money items. $450 - 800 was the going rate so I walked on by. There were lots of things to look at which you never generally see anywhere else. Lots of ex Warsaw Pack radios, including covert stuff and cryptos, a few WW2 vintage German Comms RXs, and a lot of microwave stuff.
It was encouraging to see the work the DRAC and others were doing to get young people into the hobby.
If you are combining it with a family holiday, or just like pretty scenery, fly to Zurich, then take the train to Romanshorn, and the ferry trip across Lake Constance. The Swiss transport system is joined up, in that there is not far to walk between the connections. And the 45 minute ferry crossing is just time for a beer and a look at the beautiful scenery. German hotels are inexpensive (compared with the UK) comfortable and the food is good. Lake Constance is shared by 3 countries (Switzerland, Germany and Austria) and there is an extensive network of ferries between all three. I have often gone for a week, 3 days for the rally and 4 days travelling about on the ferries relaxing.
Hope this helps,