Just tried it. it's awfully small - I had to be on the third icon from the right to get it to a readable size, which looks to be about 8pt text. The next jump up was huge.
The line spacing looked good - I could have the line spacing on the middle icon and still found the text readable; when i was using Caecilia, I had to have the line spacing on the largest line spacing for my book to be readable with tired eyes.
Other than that, it's a nice, dark, clear font. If the sizing could be fixed, I would have no problem using it.