If you like the sound, and trust the ears of the folks at Ayre, the upgrade could be a good option for you. In addition to better sound, benefits would likely include a full check-up of the DAC as well as a restart of the warranty.
I am a big proponent of upgrades of gear that I already like, assuming I trust the manufacturer and their ability to move the sonic needle - i.e., to make stuff sound better. However, with digital stuff like DACs, the technology has changed so fast that upgrading to something newer could result in a bigger improvement. Also, if you don't quite like the sound now, I would not count on an upgrade to totally turn things around since it will likely be a refinement of the sound you already have.
Consider the upgrade cost is probably equal to the amount you would get for selling the DAC used. Therefore, another option would be to sell the Ayre DAC and add your upgrade money leaving you around $3K to spend on a new/used dac. There are some pretty good sounding (lightly used, current model) DACs out there in the $3-5K range used.
I am a big proponent of upgrades of gear that I already like, assuming I trust the manufacturer and their ability to move the sonic needle - i.e., to make stuff sound better. However, with digital stuff like DACs, the technology has changed so fast that upgrading to something newer could result in a bigger improvement. Also, if you don't quite like the sound now, I would not count on an upgrade to totally turn things around since it will likely be a refinement of the sound you already have.
Consider the upgrade cost is probably equal to the amount you would get for selling the DAC used. Therefore, another option would be to sell the Ayre DAC and add your upgrade money leaving you around $3K to spend on a new/used dac. There are some pretty good sounding (lightly used, current model) DACs out there in the $3-5K range used.