I personally have the life straw bottle. Haven't had to use it (I think that's a good thing). Sawyer mini's are cheap as it is at walmart. Personally I'd like to get the grayl. I remember watching the video for the kickstarter and it seemed like a great product. Maybe I'll just look for some reviews.
I know. I hate the water bottle + filter idea, they never work well, they're heavy and clumsy, sometimes they filter as you drink and thus don't allow you to pour potable water into a cold rehydrated meal or allow you to fill multiple water bottles without having a filter on each one. I never understand the popularity of these water bottles with purifiers, they have so many draw backs. Sawyer mini or squeeze or steripen are my goto. Sometimes the MSR Guardian, but only when I know I'm dealing with really murky water, or I'm not concerned about weight.