Many years ago we took our three teenage kids on a 7 week/12,000 mile trip out West in a Airstream trailer. It became known as the Forced Family Fun trip which got better with time as they realized what all they had learned. Having added Free & Foreign & Floating & Fabulous to the original three F trip I only wish we had started earlier.
OP, GO FOR IT and do the 21 days. Now if you are going to be in LUX for several more years and the GOOD friend will let you use it again then a shorter/distance trip for the first time.
Floating Forced Family Fun!

