Been using a simple T-match ATU for my POTA activations but wondering if I should switch to a Z-match design. A well designed Z-match tuner has a high Q and is more efficient (less lossy) than other types of tuners. With only 5 watts to work with, every dB matters. Has anyone done side-by-side comparisons? My current setup is FT-818 with random wire antennas, mostly 40m and 20m CW.

Also curious about the ZM-2 vs building my own - is the convenience worth the cost for field use?

Every QRP field operator should have a ZM-2 - they do a brilliant job of matching random wire antennas and taking your resonant antenna to a non-resonant band. Worth every penny for POTA work.

Built my own Z-match and honestly the efficiency difference is marginal in real-world conditions. The first requirement of a good QRP antenna is efficiency - most verticals with short physical length guarantee low radiation resistance and net efficiencies of 10-40%. Fix your antenna system first!

For SOTA I prefer my Elecraft T1 - lighter weight and the auto-tune is clutch when you're cold and fumbling with controls. Manual Z-match is great for base station but in the field, convenience often trumps that last 0.5dB of efficiency.