Close, but the distinctions are a bit different than that. In both lines, certain pieces have disk bottoms; these are the pieces such as saute pans and saucepans that don't really benefit from straight-gauge construction. (Indeed, conducting heat up the side is quite possibly a bad thing, not a good thing, in pans with vertical sides.) In these pieces, Atlantis uses copper-disk construction, and Apollo uses aluminum disks. In addition, Atlantis uses full-diameter disks, which prevents hot spots in the corners. In other pieces, like rounded sautueses and frying pans, both lines use clad aluminum construction that is very similar to All Clad's, expect that they use thicker aluminum. The lines also differ in the handles. Apollo has loop handles that are formed from SS bar stock, and long handles that are made from rolled SS sheet stock. Atlantis has cast SS handles, that are very attractive in design. Both lines feature the Silvinox surface treatment of the SS, which makes it harder and more chemically-resistant than normal 18/10 stainless.

Congratulations on your upcoming nuptials. And how smart you are making this inquiry! You can't go wrong with All-Clad, but it's very pricey. IMHO, it's not worth the money. You can't go wrong with the private brands from either Costco or Sam's Club. My Sam's club set is tri-ply and does a beautiful job with whatever I'm cooking. The Costco set has a 5-ply bottome, but it doesn't go up the sides. Regardless, it has wonderful reviews. Go see the sets for yourself, paying particular attention to the weight and balance of the pans. Check out the prices for Le Creuset on Amazon. I have the 5- and 7 1/2 quart round Dutch ovens. (If I were to purchase them now, I would opt for the oval shape. It's more versatile.) Keep the heat down on the stove top and they'll serve you well for the rest of your life.

"Question: would I notice any difference between the stainless steel sautier and the copper-core stainless steel sautier?" Probably not. From this site (important for you to read all of it): Copper with an Interior and Exterior Lining of Stainless Steel - Otherwise similar to Copper with an Interior Lining of Stainless Steel, but the copper is fully clad in stainless steel. - Due to manufacturing considerations, the copper layer in fully clad cookware is often significantly thinner than the copper layer on comparable interior-lined cookware. This can negatively impact both evenness of heat and heat capacity.[...] Aluminum with an Interior and Exterior Lining of Stainless Steel - This design, with an interior thermal layer completely surrounded by other metals on the inside and the outside is often called âÂÂfully clad.â - Otherwise similar to Aluminum with an Interior Lining of Stainless Steel, with the addition of an exterior layer of stainless steel. - Due to manufacturing considerations, the aluminum layer in fully clad cookware is often significantly thinner than the aluminum layer on comparable interior-lined cookware. This can negatively impact both evenness of heat and heat capacity.[...] If you read through the entire article and the accompanying FAQ, you'll see the author prefers All-Clad's MC2 line (aluminum exterior/s.s. interior) over everything else in their range. And if you go that route, you'll find much cheaper brands of aluminum exterior/s.s. interior cookware in commercial restaurant supply stores. Others will weigh in, I'm sure...

gldnol: I'm in the same boat you are with the heaviness of some of the fry/saute pans. I sure wish we didn't lose what muscles we have as we grow older. Unfortunately, sometimes you have only one hand to use to to lift the pan to pour out the contents and the first time I did this the handle of the pan rotated in my hand due to the weight and I narrowly averted a big time disaster with hot liquid splashing over everything, including me. I did call the wonderful place where I had mailordered the pan and asked for advice. They sent me, free of charge, several heavy rough suede handle covers that were stitched in such a way that they kept the handle from rotating. I still don't take anything for granted when I pour hot stuff from the pan, and try to stabilize the handle on my arm, grabbing the handle as close to the pan as I dare. As far as the iridescence and discoloration: I just try not to look at it until I have the time and inclination to get out the BarKeepers Friend.