I've got a large app that was originally designed with Flex 3. That project was stalled and when it was resurrected I upgraded to Flex 4. Most of my controls are still the mx controls with an occassional spark Label where I needed the word wrap.
Due to the size of this app, I'm wondering if I should stick with the mx controls or convert all possible to the spark controls?
This is an internal app and will not have much if any skinning and should be relatively change free, once the inital bugs are removed.
The strange approach of releasing a only a small subset of the mx components into the spark library means that you are often stuck using both which I think kind of defeats the purpose of skinning advantages that Flex 4's spark library touts. Assuming that more component conversions will follow at some point, it really draws out the transition and can make it tough to justify moving a project over.
Spark is all about the skinning and not much else. If you're not going to be making use of its biggest asset, as you mentioned, then why bother? Seems like it would be a waste of time to me.