Sennheiser outlet has been refilled with some deals. These are great, lacking a few things though namely USB C port and dedicated app for tuning sound and EQ.
Refurbished available at Sennheiser Outlet for $249.95 Delivered
Also have some other good deals
Including the momentum 3 for $300 which do have app support and USB C.
Have had a good experience with sennheiser refurbished in the past so can't fault.
The Momentum 3s are also available in Sennheiser Outlet via Cashrewards for those who are interested in those specifically.
Found a decent comparison here
Last time i got a refurb it had earwax and was faulty as well. Not thanks