I have not heard very good things about the savi lights, so I steered clear of them. There are a couple newer units that have been released so I've been using the Fiberstars units. Established company with a good reputation.
Just finished a job using the Fiberstars PAL Treo lights for a customer who was unhappy with her fiber optic system. If you aren't familiar with these lights, they are a puck that's 3-4" in diameter with 1.5" male thread on the back. This makes them a perfect replacement for fiber optic systems. The fibers and lenses are removed and the light source is replaced with a transformer. The light cords are pulled back through the conduit and wired to the transformer. On this particular job, we gutted the light source and sat it back over the transformer that we mounted to a 4x4 to hide the electrical and fiber conduit that was sticking out of the ground.
Anyways, the customer was extremely happy. I think her hot tub can probably be seen from space. Zodiac is about to release their own version that will be very competitively priced with the Fiberstars units. I will probably start to use those, as I prefer the way that they mount into the wall. The zodiac units will also be compatible with older aqualink units that will controll the old watercolors lights.
For anyone who is thinking about replacing their fiber optic system, I would highly recommend either of these options. You will not be disappointed.