Well, I decided to call ATP and find out who else they provided intakes for, and how long they have been supplying APN. They have been supplying APN for several years, and Rock Auto also sells their product. They do not supply Dorman. Below is a page from the ATP supplemental catalog. If you were to buy from Rock Auto, you would pay 134.89, but you would get that fancy case also. I paid 94.00 from APN and it came without the case. I don't know why anyone would need/want the case.
1999 SSE. 108K. Cleared Corners, Mobile 1, Energy Suspension endlinks. Ported and Polished LIM, NGK TR-55 Sparkplugs, 180 drilled Intense stat, Flow matched injectors, Intense FWI, Intense PCM, MagnaFlow Cat.