Rich
Hardware is more cumbersome to update than software. Also, the differences between v3 and v4 aren't huge. Mainly a different audio amp, I think. If your v3 is working, that is great.
All v3 and v4 boards tend to have spurious out of compliance, maybe v5 might also. Our local club kitted a relay board and a filter to address spurious, other possible solutions are out there.
Folk are experimenting with power flatness. For ssb it might lead to more trouble to try it. My v4isn't to bad in its behavior from more than 10w on 160m to around 4w on 10m. I think effort is better spent elsewhere for getting only a fraction of an S unit.
Enjoy your ubitx journey,? it's a cool rig.
Curt
