6.25m is perfect for solo
6.7m is getting up there
Just make sure yu are set up so you can easily drive the boat on and off the trailer
I have some tips here on how I set mine up for quick and easy use - has served me well for several years now without a problem
http://www.ausfish.com.au/vforum/sho...ving-a-Dunbier
Just get what you want - set it up right and enjoy it!