Yeah, I could have been a whole lot more impressed with CA's trade-in allowance.
So I've just kept the Pro as a backup. To me, the best improvements with the Pro Plus are it's durability, and vastly superior microphone. I always felt the mic 'sweet spot' on the Pro was too tiny and it had to be positioned just so, or it would affect my transmissions. The increased ruggedness of the Pro Plus makes it ever so slightly less comfortable than the Pro, but still perfectly suited for a transcon. Your melon may vary...