Updated: Dec 3, 2019
To avoid Spoilers, I've only shown the set-up here and I'll avoid any giveaways in this comment. For a couple of us, it was our third Exit game and for two it was a first. To avoid giving anything away to those in our group who might want to play it later, we locked ourselves away in a small ante-room off the main hall. We were secluded there for so long that the rest of the group started to send in rescue parties!
Tho' our progress was slower than in previous games, the experience was in many respects the more enjoyable. The puzzles varied hugely in difficulty - some we solved almost instantly while others had us agonising (overly, as it turned out) over interpretation of the minutia of wording. For those who'd played the other Exit games, there proved not to be any meta-gaming advantage, other than our confidence that it would be an utter waste of time looking at any of the top clue cards (we were confident they would do little more than restate what was already blindingly obvious).
If you haven't yet tried any of the Exit games, then you need to think of them as a group puzzle-solving experience in a box that are intended for a single one-off play and then discard. It isn't just that you probably wouldn't puzzle much over a riddle a second time around, it's also that you can expect to mark, damage or destroy components to complete the game. It's a relatively inexpensive purchase (typically around £12), so think of it not as a game to cherish in your collection but as the price of an evening's entertainment for a group (it's probably best with 4-6 participants). There are more Exit games due to be published next month but if you're just looking for one to sample of the three published so far, then The Secret Lab is the one to try.