I stayed at the Sheraton Maui earlier as a gold and returned as platinum. There is a big difference. As platinum, I was upgraded from resort view to oceanfront and had a free breakfast. The treatment was great. Earlier, as a gold, I booked a resort view and was shown a room that the cars drove by and no view. I was told that I could be upgraded to oceanfront with breakfast at the Sheraton Club for $110 a day that I accepted since the offered room was really bad.
Marriott treats gold and platinum almost the same. Now with the additional United people, the CL are very crowded and uncomfortable. I guess selfish since I have lifetime platinum, I hope when they merge the 2, they stick with the treatment as SPG does. SPG also offers a guaranteed early check in as early as 10am as well as a late checkout of 4pm.