Sounds like fun. Haven't been on one myself but have been planning to do a similar road trip down to Italy to see the Mille Miglia, but plans have changed this year.
I'd go for it. I'm sure you'll have a great time, just heed the advice of a previous participant (taken from their Testimonials page):
TEAM NACHO AVERAGE SQUAD
Fantastic, great company, very well organised. Nurburgring is a must, just don’t crash.