I do find DAC buying frustrating. Buy a kickass preamp, and it will be a kickass preamp for 15 years before you're lusting after something "better". Buy a kickass DAC, and it will be for 3 years, if that.
I know, it's the same thing that you listened to and loved. So there's no reason why, the fact that now people are gushing over how much better XXX DAC is, and it's half the price of the one you bought, should change the fact that your DAC still sounds the same and you should still like it.
But it is more like buying computers and smart phones, as good as it is now, just wait. I was perfectly happy with my old Blackberry. But it couldn't allow me to respond to work emails, and also measure the wow and flutter on my turntable, and index my wine collection with the snap of a photo.
Given the new generation of chips, and all of those smart designers out there just starting to play with them now, I can't help but think this is one of those moments when a little patience with that old DAC might be worth a year or two wait.
Something even better will doubtless come out in 5 years. But I think I'll hold out for a few now before demoting my current DAC to system B.