I had a Motofone (also called F3) for the last 7 years. It started with a two week working battery life. It's a pain to text message on since it only shows 4 or 5 characters on, but it just worked as a reliable phone. Finally switched to an iPhone 5 after it became vital for me to have full Internet access 24/7 for work. If it weren't for that, I'd still have my F3. I love it as much as I love my iPhone 5.
You can still find some of them on eBay. I'd offer mine, but I'm keeping it as an emergency (911) phone for my car.
F3 to iPhone 5 has to be the biggest jump I've heard of lately. I've been meaning to pick up a dumbphone myself, maybe I'll grab an F3 - I remember when they came out, I was dying for one. It's a bit like buying the... junker of your childhood dreams.
You can still find some of them on eBay. I'd offer mine, but I'm keeping it as an emergency (911) phone for my car.