I don't call my 2013 rmbp a money maker. But I only use this one computer for both work and home. I really want to try out Yosemite tmr. I'd like to show you the apps I often use. Would you help me out by checking if they will give me any fatal crash or serious problem? Thanks in advance. Daily: Safari, iTunes, Messages... Email: Apple mail for @me.com. Air mail for business. Work: Pages, Numbers (I use them very often for work). Sometimes for communicating with Windows users, I use Word and Excel. Chrome. Entertainment: Youtube Misc(not as important as the lists above, but I'd like to see them work): Evernote, iBooks, Steam ---------- BTW, I have Time Machine backup of mavericks. Will I be able to recover my computer to Mavericks, if beta can't be used?