I like the spa and the vibe but to me they offer very different services. The spa is tranquil, promotes relaxation. There isn't a bar in the spa. Its totally focused on relaxation. But it can get crowded and lounge chairs can limited. Vibe-generally has more activity. There is a bar and you get to know the bar tenders and the servers pretty well. Drinks are well made -well at least in the past. We have joined groups at the bar and have had fun. There are generally plenty of lounge chairs! And as someone said the servers come around with fruit and other things.
If you have the extra money and want to try it then go for it. Then you know. Same with the spa passes. I have enjoyed both the spa pass and the vibe but as I said they offer different "vibes"