Thanks for the great input. The Rizzini Artemis is also a gun I was considering, but really want the CG Magnus. I will continue searching for one hoping to buy used to save a few bucks but may have to bite the bullet and buy new.I have two 12g and one 20g Magnus Limited Fields and they are beautiful guns to shoot. The balance and fit is perfect for me. I can practise three rounds of skeet with the wood butt plate and feel no effects of recoil.
I do not have the 20/28g combo in the Magnus but I do own two Tempio Light Fields in 20g and 28g. They are both built on the 20g frame and are very close in weight. The 28g feels a bit less whippy than my 28g Rizzini Aurum Light which is built on a scaled 28g frame, but that is only noticeable when comparing them side by side.
Personally, if I were to have only one gun for the shooting I do, I would go for the Magnus Limited 20/28g combo.