I have been very pleased with FF4 so far. A few of my plug-ins no longer work but that's to be expected. It's a nice looking, quick browser that still uses more memory than I would like but I suppose that's why we all have 4GB+ of memory on our machines.
"It is far better to grasp the universe as it really is than to persist in delusion, however satisfying and reassuring."
- Carl Sagan
Intel i5 2500K | Gigabyte GA-Z68XP-UD4 | 16GB G.Skill DDR3 | Crucial M4 128GB SSD
WD 1TB Black x1 | WD 2TB Green x 1 | EVGA 660 Ti Superclocked | Corsair H80 Water Cooler
Fractal Design R3 | Windows 7 Ultimate x64 | Dell 2410 x 3 @ 1920x1200
Intel i7 920 @ 3.0 GHz | Gigabyte GA-EX58-UD4P | 24GB Patriot DDR3 | WD 1TB Black x 2