The beauty of a water ballast boat is that it is light for trailering (unless you forget to drain the water) and so you can trailer a larger boat with a smaller vehicle. If that is important for you, then go for it.
The reason people tend to say they are tender is because the water ballast is less dense than other ballast materials and it is up high in the tank contained within the hull. A boat with ballast beneath the hull can offer greater stability and, of course, that is in the form of a weighted keel of various designs. Because of the presumed tenderness of the boat, the manufacturer often shortens the mast up to lower the combined center of effort of the sails being used.
A taller mast, of course, is the horsepower of a sailboat. So, when you shorten it up you lose sailing potential in terms of performance. Someone wrote that his water ballasted boat sails very well when reaching. Well, any boat sails very well when reaching. If you are looking for stability and performance, the only water ballasted trailerable boat that I know of that is a real good sailing vessel is the Schock 23. They made two 23-foot models and both are good boats, but only one of them had a water ballasted hull and it was faster than the other. The other had more interior space and is a fast boat, but not fast like the water ballasted boat, which really is built to race.
There is a couple who own a Hunter 28 water ballasted boat and I think they enjoy the boat ok (it has a big interior and comfy cockpit) but whenever the wind pipes up, they are the first to reef to sail the boat flat. The boat doesn't sail very fast at all, but they aren't in a hurry, I guess.
I know of another person who came out of a very stiff 22-footer and got into a Hunter 260 to accommodate his growing family. The first thing he said, was, it was ok, but real tender and his wife didn't like that. He soon bought an S-2 30 and forgot about trailering his boat.
So, I guess there are compromises to anything, but if trailering a light boat is a top priortiy, the you, in most cases, might have to sacrifice performance and stiffness in a vessel.
The other issue with a water ballasted boat is the ballast tank is in the hull which takes up interior space which means the hull freeboard (sides) is often much higher to keep the interior space that sailors who buy these boats enjoy. The creates windage under power in a marina and sometimes you can be blown around and in a tight spot, that can cause problems sometimes. Where there are a lot of manufacturers who offered water ballasted boats, I think most are getting away from that concept now.