I'm so glad I came across this thread! I enjoyed reading all the comments.
For those of you who are unsure about making the trip, all I can say is just do it! And don't wait until you are too old to enjoy it!
We made the journey from Georgia in 2013. Our trip was over 14,500 miles pulling a 35 foot fifth wheel. Yes there are places where the roads are bad but as someone else said, it is a small price to pay for the experience! My only regret is we didn't go when we were younger.
Our favorite place was Haines. The most exciting thing we did was take a flightseeing trip from Talkeetna and land on a Glacier. A really fun excursion was taking the Hurricane Turn train ride on the Alaska railroad from Talkeetna - I highly recommend it. We left our RV in Fairbanks and drove to Coldfoot and back in one day. We drove from Dawson City to Chicken on Top of the World highway. I could go on and on.
Click the link in my signature to visit my blog with posts about our adventures and maps of where we went.