I like them - they're quite a nice departure from the typical "rooms and corridors" look that's so ubiquitous.
A few issues - first, they might be a bit more legible if you used '#' and ' ' or '#' and '.'; if you're concerned about character width, you can use [ code ] [ /code ] tags in the message, like this:
#####
#...######
# #
Second, diagonal corridors don't always make for good gameplay - if the map is unknown, then while the player can see all the floor tiles from one end of the corridor, the corridor walls could be out of line of sight. I'd recommend either choosing a very permissive field of vision, widening the diagonal corridors, or sticking to orthogonal corridors. Of course if the whole thing is visible from the start there's no problem.
Third, just my personal preference - it looks like the graph of connectivity between the rooms is almost a tree, that is there aren't many looping paths through the dungeon. This means there are lots of dead ends for the player to get trapped in, it takes a lot of backtracking to fully explore, and in general the shortest route between two points in the dungeon could be quite long. Again, there are some cases where this isn't a problem, for instance if the player doesn't need to fully explore the level, has more than one option for where to leave the level, or if teleporting is cheap, etc. etc.
