Toro is the best, but only if its real. What they have at the 100 yen sushi shop is NOT real. Its regular fish meat soaked in oil. Its not bad tasting, but it should be illegal to call it toro. Its not. The real thing is expensive. I have had it. Its excellent.
At the cheap sushi places, I like what they call "saamon" which is salmon with fresh chopped onion and mayonnaise on top. Next would be hotatte (scallops), whether plain or carpaccio (misnomer) and then just plain old tuna.
Hardly ever eat sushi or sashimi anymore. Never know how close any of it has been to Fukushima.