TDO = Top Dressed Otohime. ChromaBoost is basically Otohime with Haematococcus added, which provides a color enhancer (astaxanthin) and supposedly more nutrients. I'd be curious to see an experiment done where half a batch is fed normal Otohime and the other half ChromaBoost so we can see how much of a difference ChromaBoost makes.
Anecdotally speaking, if you're looking for the best colored clowns, then spend the extra to get TDO. I personally think it's a non-issue because Reed no longer sells small packs of regular Otohime anyway. I just bought the breeder pack and its lasted forever. When the clowns get larger I add frozen food (Rods and LRS Fish Frenzy) to their diet so the larger sized pellets last even longer.
I do the same as shifty where I feed rotifers for about the first week, and then sprinkle some size A into the tank. Apparently the don't each much of it, they just get used to how it smells and that it's at the surface of the water. I skip BBS altogether. To be completely honest, you really don't need size A either -- you can get by with a larger size -- just grind it or rub it between your fingers and you essentially have size A.
I don't remember which stores in the Bay Area sell TDO, but I've seen it before. When I need something from Reed, I just ask my LFS (Aquatic Collection) to order it for me and then I pick it up when it arrives. It saves me shipping costs though I typically spend that amount while I'm at the shop anyway. Support your LFS!
Depending on where you are in the Bay Area, you're welcome to swing by and pick up a little bit of TDO A if you want to see what it looks like. Just send me a PM.