The EVA lounge is quite nice, especially the ice cream fridge, but I much prefer the SQ lounge on the other side for their food. The selection is a tiny bit less but I find the quality much better. In either case going to the other side for one lounge is a LONG way to go... About the TG business lounges... be careful I got food poisoning a couple times eating food there! I would take either the EVA or SQ lounges any day.

And yes the Amex Plat card is the EVA branded one only, it's a set of specific benefits such as priority check in and lounge access you get with that card.