Of course you won’t have a personal guide but it’s well worth the $50 for me. I’ve been pretty lucky at customs a bunch of times and only had to wait like 10-30 minutes but that fast track has me spoiled. 😆
Here’s a solid tip for you; if you’re a traveler through BKK a lot like I am as I go back and forth to visit my kids back in the states about every 6 weeks or so, it’s worth applying for global entry and adding on APEC(Asia-Pacific Economic Cooperation) for an extra $50. That APEC card allows you to get waved on through the fast track line for free. I use it all the time.