Is a Chromebook a good buy?

I'm looking into buying a computer for my mother, she's not very tech savvy, heck she still has problems understanding her iPhone 4S, but she need a computer to manage her husband's business, who is even less tech savvy than her (the man still uses flip-phones) she been hinting at me that she needs one, I've tought about tablets, but I dont think there would be enough apps and ease of navigation around the UI with a tablet, when she's still trying to fully understand her phone, a Macbook or iMac would be too expensive and too complicated, and I'm not even gonna go into why Windows 8 is out of the question, but Chromebooks are pretty much just a browser within an OS, no? so I was just wondering if the difficulty of understanding how Chrome OS works is easy enough for an elderly non-tech savvy person to use, without making it too stressful for her?