I'm running the latest version of Mountain Lion on a late '10 MBA 11" with 4 GB of RAM and an OWC Sata II 240GB SSD. I've even wiped it and started over. Mail lags horrifically. Like up to five seconds sometimes. It's like it has to catch up every now and then. I'll be typing an email, and it'll just stop for several seconds...and then the whole sentence I've been typing will appear quickly as if it's being typed. The worst part though is scrolling through mail. It takes several seconds for *any* email to appear in the pane when I click it. Any ideas? The only other app that behaves like this is Wunderlist (and it's even worse...complete lag 100% of the time as I type).