Great article on CSS-Tricks about using and dealing with WordPress Transients. Covers setting and retrieving them as well as other WordPress Transient tips and tricks.
The always insightful Justin Tadlock has posted a great post on how best to handle stylesheets in child themes. Though there are many options for this, including the infamous @import technique, Justin recommends loading the styles directly from the parent theme itself. It’s a simple but effective solution that should work for 99% of cases.