I've had one other person mention that it makes no difference between the solo and 25 man panels and that has me utterly confused. The cause of the FPS leak is a problem in how the buffs and debuffs are handled while in combat.
In the 25 man raid panel, the system is trying to track several hundreds of auras at any given time. In the solo panel, it's only tracking a few dozen. If it makes no difference between the two panels, then there's a problem other than the FPS leak going on.
What people don't get is that I am, ultimately, an artist at heart. My brush has two colors, 1 and 0, and my canvas is made of silicon.
I know for me it goes back and forth. Some days, switching to the solo frame helps tremendously. Other days, it does very little. I'm sure it might have something to do with other addons I have but I have done enough clean installs and one by one additions to know that it's not just one addon. Lucky for me I have a decent enough internet connection at home that I can survive through the drops to 5fps even when healing. I have gotten good enough and used to the drops that I can tell whats happening even when I'm lagged out (at least to some extent).
I am eagerly awaiting the alpha and will be right on top of that to help test it and whatnot. As always, keep up the great work Scott.