I've been here 3 times within a year and I'll actually be going back for my 4th time next week. If that doesn't indicate how much I love this place, then I don't know what to tell you. Tea Lounge at the Mandarin Oriental is by far the best high tea experience I've had. I know there are other locations in the Vegas area that offers high tea which I have looked into but none seem to be on par with how elegant Tea Lounge is as well as the view of Vegas.
Tea Lounge is by reservation only so plan accordingly and book your spot in advance. Each reservation is given a 2 hour window so that you are able to enjoy your experience. The lounge is located on the same floor as registration and it's in an open space outside of their bar. Considering it being in an open space, it's still really intimate and has a very tranquil vibe to it. The staff have always been amazing and accommodating each and every time I've been there. From assisting with tea selections and explaining the items on the display. They do your first pour of each tea which is a nice touch.
The best way to enjoy high tea with your friends would be to each order a different tea and try each others. That way you're able to taste everything. As for the display, it doesn't seem like it would be enough food but it is actually quite filling. Especially with the amount of tea you consume with your display, you will be satiated. It's about $45-$50 per person for the Afternoon Tea which includes a pot of tea and the tiered display. If you would like champagne with your high tea, they do offer that option for a little bit more. For the overall experience, I'd say it's worth the price. I've paid it multiple times and I'm a broke college student. So I'm willing to go a week without groceries to have fancy tea then you know it's legit (haha). With all jokes aside, this place is worth every penny for any occasion. Enjoy!