We did Alaska on our own with our 3075 in the summer of 2008. We even did the Top of the World Highway. You can read about it on our blog the dates are June 1, 2008 thru October 1, 2008.
http://birdingrvers.com/
The roads that are actually in Alaska are better than a lot of roads in the lower 48. The worst stretch is from Haines Junction, Yukon to Tok, Alaska due to frost heaves.
The key to driving to and from Alaska is to SLOW DOWN. There are no 65 mph highways. When you see construction or frost heaves drive even slower.
We have never caravaned but, an advantage would be you never have to worry about where you are going or where you are going to stay next. The disadvantage is if you don't like the place they pick you have no choice.
The real advantage to not being with a caravan is that you can extend your stay at a place you like or if the weather is bad.
When we went in 2008 we had already been to both Fairbanks and Homer so only planned to spend a few days in each of them. The weather in Fairbanks was the best we had all summer so we stayed there for two weeks. Homer was paradise, we extended our stay there to three weeks and would have stayed longer but, it was almost Labor Day.