Edit - looks like they are.
Funny thing is the 'regular' S-335 stainless model also comes with the 7mm grates. I have a feeling weber had some surplus stock of the older style stainless grates, and that's how the SE model became a thing.
The special edition doesn't come with iGrill. To add it in after the fact (and have four probes) would cost you $150 if you decided to add it afterward
The special edition also doesn't come with the cover. That's another $90
Also - the one thing the Costco-only model doesn't have is the motion-activated handle light. You can add that for 30 bucks after the fact if you wanted it. Can't add in the lighted knobs afterward. (Well, at least not easily)
However, none of that solves the fact that you want to use natural gas. If you still want NG right now, then it's still a good deal. I also have the urge to convert over myself - but after eyeing this one for so long, I'm glad I just went through. Down the line i may still convert it.