Firefox and IE have the best HWA IMO but Chrome’s HWA is almost non-existent. Maxthon’s and Opera’s aren’t complete and Safari doesn’t have it on Windows.
I do agree Skia is a great software library in terms of speed but Mozilla are concerned about the HWA side of it. Opera probably want to have their own implementation to make it their own work.
The core updates for Opera are well received by me and I’d be happy to see some of the issues fixed – like some performance issues others are having and the ability to drag a URL or an image into the tab bar and open it in a new tab.