Hi there
The one I got a year and a half ago didn't have a Swiss 7750 in it, it was asian. I seriously doubt you will find one with a gen Swiss 7750. As a Swiss 7750 is around 350 USD at least, 217 USD for the watch with a gen movement inside isn't a credible offer.
The only flaw ever fixed was the wrong coloured chrono hands (they were changed to white), the dial was never changed. It is highly doubtful anybody will fix this as this model is discontinued by IWC and the newer 3717 rep is so good it gets all the attention.
The worst flaw compared to the Gen in my opinion is the wrong case: the rehaut is too steep. This will also prevent you from using a gen dial, which you can buy regularly on the Bay. The gen dial is too small because of this. I know there are people who tried a workaround to use the gen dial anyway but I have never seen an actual franken of the 3706 flieger.
I like this watch very much but the flaws of the rep forced me to go gen very soon.
Kind regards
Val.