Is there any value in a spin class?

Just curious. My old trainer makes tons of noise so I've been logging some time on the gym's spin bikes. A couple times I inadvertently overlapped with a spin class. They were... interesting and seemed good for getting some high intensity in but they seem majorly biased toward z5 rather than z4 (I hit maxHR 8 times today). I also don't see the value in all the standing and pedaling that seems to occur. My plan had just been to hold a small base for the next few months so I'm not really concerned about optimal training and it seems like it might be fun to make my weekly long ride something like 1 hr z2, 45 min spin, 45 min z2