How many years is a flagship component good for?

15 minutes, as the hi end business model call for better to be available right after you purchase it. Among my antiques is a forth year old Kenwood solid state unit that puts some of the current solid state stuff to shame. You figure.

Until the new flagship comes out - unless deemed an audio classic by desireablity of the educated masses then until it is surpassed by better technology.

odds are a 15K preamp then would be like a 25K preamp now. (both are way too much for any preamp, imho)

I would put my $350 Accuphase C-200 up against any new pre and it's almost 40 yo

Stanwal, are you using Martin Colloms's arbitrary ratings as some sort of objective indicator of performance levels? That scale of his is a bit of a laugh, and based entirely on his subjective tastes. It can't be taken seriously.

Statements to the effect that a $15K premp is like a 10 y.o. $25K preamp are nuts; there is no scientific correlation between price and performance, or between age and performance. Forget such comparisons. Remember, good engineering costs no more than bad.

As always, if YOU like a piece, use it; your ears are arbiters. That said, old gear needs freshening if technical inspection sees performance dropoff.