I haven’t made any scientific comparisons, I only share my experience. I’ve been a devoted Mozilla/Firefox user for many years. My current workhorse is an AMD Phenom Quad core box with 8GB RAM and it flies.
I tend to keep 40-60 tabs open, on average. I can run the latest Firefox on this box and it will have severe performance problems (the screen turns grey, desktop unresponsive) even with nothing else running. I have to restart Firefox 3 times daily. It takes a long time to reload, so this is a major inconvenience.
I am now running Chrome with 42 tabs, as well as Thunderbird, Gimp, Pidgin, 5 terminals, and 2 virtual machines (Ubuntu 10.4 using QEMU and OpenSuse 11.2 using Virtualbox 3.1) – all this on a fully pimped-out Compiz 3D desktop on a 24″ display – with outstanding performance from Chrome.
I love the Fox, but until it gets its act together, I’m using Chrome.
Anyone who knows me, or knows of me, is aware that I use Free and Open Source Software; painfully aware, in fact. I never shut up about it. The torrent of sarcastic anti-Microsoft remarks must get tiresome. The inevitable lecture on the advantages of FOSS over proprietary systems is endured (usually) with patient grace by my friends and family. Although, I suspect, they stay on my good side so that I continue to provide free tech support.
So why, why am I using a proprietary browser?
It’s simple, really. It’s better. Working on this ten year old Dell PC with Ubuntu 7.10 GNOME desktop, struggling along with 256MB RAM memory and 6GB disk space, Firefox (my heretofore favorite browser) just isn’t cutting it. The memory leaks, freezing and crashing are too frustrating. I’m not a religious man. I’m eminently practical. I use what works. Given a choice, I’ll always choose a FOSS solution. But I will always choose the best solution, for myself and my clients. For a Web browser, that solution is Opera.