How will the set up be as I am a little confused with how you will be using the Z Walkman within your current gear as you are asking about static and wireless streaming.
Are you going using your Z through the speaker set up, through headphones or both?
I get the impression maybe you will be using it as a music jukebox hub through your Arcam speaker set up rather than with headphones?
I also have Arcam, a FMJ DVD player with Chord interconnects through Tag Mclaren processor and amps with B&W CDM SE speakers all round.
I used to have a Naim Headline amp with NAPSC power supply which I used my Sony X series through the line out to listen with my then AKG K702's which was good, but now since I have gone portable with a pair of JH16pro monitors so wanted a portable amp and got the Ibasso PB1 with the DB1 Dac and for such a little box there is a noticeable difference using this with both a laptop or the X Walkman which by the way has a very good under rated built in digital amp which the Z series is reported to have improved upon from those few who now have a Z to compare to their X Walkman.
So a Rega dac or Music fidelity dac sounds a good bet even though a lot of money to invest in a dac if just solely for the Z Walkman especially if you went for a Leema dac in terms of the price. If you will be using other sources in addition through the dac it makes it more palatable in the purchase.
I even used my Arcam FMJ direct through the coax out into my Ibasso dac and amp with my earphones and was impressed with what I was hearing.
I am not sure about the streaming side of dacs in terms of quality/ reliability, maybe some one else who has one can chime in.
How would you use a wireless streamer dac if you had it within your set up then with the Z then?