Is low cost DAC worth it?

Been learning a lot from you fine folks... thanks!

I am driving Boston Acoustic Lynnfield 975 speakers with a Willsenton R8 amp (recent purchase to try it out) and streaming over wifi through Apple Airport Express. It sounds pretty good but I find myself wondering if adding a low cost DAC would improve the sound any?

Maybe something like the Cambridge DacMagic 100 or 200M?

My hearing is not that great anymore, so I don’t think it makes sense to jump on a DAC costing thousands, but I understand the Airport Express is a decent DAC, so not sure if a low cost one would make any difference?