Hi Kirill,
It's great to see such huge performance improvements in substance5. As I'm already using java6, I'll give it a try tomorrow with my application.
Probably, laf-plugin's xml parsing can be replaced with ServiceLoader, as now java6 features can be used. Although, I've not tested it's performance, it should be faster than xml and IMO, more neater. Hope it'll further improve the performance, when many plugins are present like substance-swingx, flamingo, etc.
Maybe it's already in your roadmap, but thought to just leave a note here.
Thanks and Regards,
Prashant