This is an example of the designer making a thoughtful improvement,? and perhaps finding a good deal on them. They may nudge the clean output power up a little, but honestly I added an LC filter at 45 MHz to address spurious on my v4, and I am still happy with its output power. On receive it might reduce noise figure a little. But if you live with neighbors our background manmade noise even on 28 MHz can be higher than the 10 or so dB noise figure of the ubitx.
I don't suggest putting money or time into this mod, unless you live in the desert with few people around.
Curt
