The Chicago offer is unbelievable! Assuming it is for the full dinner, the dinner alone retails for over $680 for 2 (this includes tax and tip), and probably over $900 with the wine pairing, not to mention the cocktails and the gift, which I'd guess is a cookbook. See https://www.chase.com/personal/credit-cards/british-airways/above-beyond/International-culinary. Based on your valuation, Lucky, this package is at least 60% off regular price and probably closer to 75% off. Even if you have to tip or pay the tax, which are included in the retail price, it would still be a good deal; however, I suspect that the gratuity is included and there will be no tax.
I would definitely try to get the package, but I recently booked that dinner at Next for a night in October when I am in Chicago, and I don't think I can get the card and the Avios in time to go again because the offer will go very quickly on the sale date. Lucky, you should try to get the package if you like exceptional food. It will definitely be worth the trip to Chicago -- and your savings will pay for the travel. This is one of the top restaurants in the world. It will be even better than your beloved First Class airplane dinners! 🙂 You can thank me later.