My thoughts ...
I hope you are referring to this one, found in an old catalogue.
The naming of this particular model is not 'right', as a Sport, it is more of a evergreen classic. In term of proportion, the Square case is pleasing versus the current rectangular case due to continuous flow of the lugs-design.
The previous design, could observe the "bulge or embossed" of the bezel and the bracelet, whereas the current is more streamlined and "flattened".
So if basing on design I prefer the previous congruent classic design approach. Somehow it reminded me of Cartier.
Not sure if you are looking for a Sport piece for your Lady, as you are shortlisting Happy Sports.
Otherwise, would encourage you to look at the new Imperiale line with mechanical movements, but without the whimsical dancing diamonds
Most importantly, does She like it? Our inputs are actually secondary, I feel.
Kong
Without seeing both versions
I can only make a generalisation about Chopard and the Happy Sport range.
The older model should be good quality. I won't be drawn into a Then & Now debate but generally, between 1963 and 2012, when comparing an old and new version of the same model at Chopard (new old stock), go for the older model....more bang for your buck.
Any Happy Sport with the dancing diamonds is good. The owner and nearby observers will be so entranced by the dancing that they don't care so much about the case / bracelet.......believe me!
Regards,
MTF
PS. I even wore a black ceramic version to the Chopard-sponsored go-kart racing at our 10th birthday party in Las Vegas.
Mr KFS (LUC President) was a bit worried about me as a man wearing a ladies' watch to a racing event. But hey! Whatever rocks in Vegas..... stays in Vegas.