i've got it on a USB drive. Slow, but i'm sure my personal data will be fine. Plus it lets me try it out on various Macs i've got around me! a 2007 and 2012 iMac and a 2010 macbook pro and a 2013 retina macbook pro
I am using it as my daily. I have complete backups of Yosemite with TimeMachine and CCC, should I need to revert. At this point, I am not loading the system with everything that was on before. I am keeping lean with apps and files.
Just curious what would your opinion be on installing the El Capitan beta on a Thunderbolt 1 external mechanical hard drive. What kind of performance would I get out of it booting from that?
I'm tempted to do my initial testing there and then once I am satisfied that all my core apps are working I will upgrade my iMac. The only reason I wouldn't install El Capitan in a virtual machine is that I find Mac OS X performance to be terrible virtualized compared to Windows. Mouse lag left and right even with half of my iMac's graphics power directed towards it.