Tikenyon:
As Mike stated, you'll be fine in a R25 for the Great Loop. As long as you are used to being in your R25 for longer stretches of time you'll have no problem. The advantages of doing the Great Loop in a smaller boat like ours are more docking options, less costs for docking, less insurance costs, more anchorage options because of shallow draft with the added benefit of being able to trailer your boat. Take as much or more time then you plan, as doing the Great Loop is a wonderful adventure.....minimum 1 year or even break up into several years if you're able to swing it is even better for exploring and immersing yourself in towns, villages, cities and areas like the North Channel, River system, Keys, Great Lakes and the Chesapeake Bay to name a few.
Jim F