IWC ,with lot of choices especially your budget is $40K,less fake watch.
Panerai, all face (dial ) too similar and too many fake watch.
Bvlgari ,too fashion and not a pro watch making company.
my personal opinion,pilot series,but actually,your budget can buy any IWC you find from the watch shop.So I suggest you go to visit yourself.Aquatimer series and Ingenieer series are also hot.You can specificllyask thm any limitded edition watch they have,which will make your one more unique ma.