We went during All-Nighter Festival (Nuit Blanche) this past weekend and made it to Santropol as one of our last stops. Sadly, they only served hot chocolate, soups/chili, and cakes at that time, so we didn't get to try their renowned sandwiches.
We split a chocolate cheesecake. That was pretty good and surprisingly light (almost like a mousse). My friend had the hot chocolate, and they topped it with whipped cream and fruit (unusual). She said that was great.
The place is definitely very cute. A lot of figurines and interesting decorations all over the cafe. I can see how the garden would be nice during warmer weather. I'd definitely give this place another shot.