Interesting topic, I have to say i was in love with prepros when I found it and it worked great on my windows machine at work.
I recently got a Macbook Pro as well and wanted to stick with it but after a couple of day of having issues getting compass support on it I decided to try codekit and I have to say from my initial use codekit does seem to outperform prepros, and is so simple to set up.
I hope either code kit gets windows support or prepros can simplify its compass support on mac.
Also having trouble with Prepros’ connection to Compass. I’m not an expert on Compass but I wonder why Prepros uses an alpha release of Compass (1.0.0.alpha.19) when the current version seems to be 0.12.2.
This causes problems when I’m using frameworks that were built with older Compass versions in mind (specifically in my case, the Zen theme for Drupal).
Another thing is that Prepros sometimes just becomes unresponsive — happens to me at least once a day — but I’ll give it the benefit of the doubt and blame my computer for it. For now. ;)