I think you may easily find a DAC that provides a significant improvement to the sound quality, depending on what it is you listen to and prioritize when listening to music. The BDA-3 would be a big improvement over the BDA-1, in my personal opinion. But there are lots of other DACs out there that you may prefer.
Move on from my Bryston BDA-1?
Given the advancement in DAC technology would I achieve a noticeable (started to say significant) improvement in audible performance by upgrading from my current (but early generation) Bryston BDA-1? I am hesitate on the assumption that the internals of the Bryston (e.g., power supplies, output stage) are still hi-grade but understand the CS-4398 chips have been surpassed. I should mention in the system I stream from a Bluesound Node 2i (and in another use an identical streamer with a Topping D90 DAC).