To be honest, on a Greek Isles cruise I would not get either. There is just not enough time to enjoy them. I typically get the Thermal Suite pass but on my Greek cruise in November, I honestly would not have used it. Our days from dawn to dusk were pretty much spent off the ship. I have never been in the Vibe (not a hot tub, lay in the sun person) but from what I have been told by others, there are plenty of loungers. I was on the Escape in February in a Spa Balcony and the only 2 times I tried to use the Thermal Spa, there were chair hogs just like on the pool deck and the pool (which I have never really seen anyone swimming in) was packed. I have never had that experience in any of the other Thermal Spas I have been in (which are Getaway, Bliss, Encore and Pearl). I think if it was an either/or I would keep the Vibe pass and try to get a day pass for the thermal spa.