i don't think there is a player i'd rather own ad infinitum than trout and i wouldn't exactly call tulo an insane price. feels more like a medium sell high/buy low. it's worth pointing out that it's possible we've seen the best of tulo (he's 27, the generally accepted "peak" for hitters) and the regularity of injuries are, of course, a big red flag.
however, deciding whether to "sell high" on trout should also depend heavily on your place on the win curve. can trading trout put you over the top this year and next? also, what kind of player do you see trout being in 2014: 15/45 or 25/60?