Our number one 'best wireless keyboard' recommendation is the Logitech G915 TKL, and today this compact mechanical keyboard is £50 off at Amazon.
That makes this ultra-premium keyboard significantly more affordable, dropping the price from £199 (!) to £149. It's still a premium proposition, but in my eyes it's justified by the robust aircraft-grade aluminium design, low profile tactile mechanical switches and industry-leading low-latency wireless.
These basic elements are enough to make for a great keyboard for typing, programming or gaming, but the G915 TKL gets a lot of the little things right too.