Correction: I have the Sweetwater. Either way, you can't go wrong.
Depends on what you're using it for. If you're going camping, I recommend anything by MSR, including the MiniWorks MiniWorks. The Hyperflow consistently gets editors' awards. I have the MiniWorks, and I love it. It's quick, the water tastes clean, and it's easy to care for.
Correction: I have the Sweetwater. Either way, you can't go wrong.
If you're looking for something to purify water while backpacking, I'd ditch the filter altogether. Iodine (or similar) chemical sterilizing agents work just as well, are a fraction of the weight, and require much less effort.
If you find the taste objectionable, you can either deal with it (your backpacking, after all), or buy some of the neutralizing tablets. It's just vitamin c, but it eliminates the taste and color of iodine treated water.
I am using the Katadyn Micro Bottle Filter. It's a 3-in-1 awesome worry-free thing, that can be upgraded if need be. I'm doing a lot of ATV'ing along Great Slave Lake in Canada and this bottle is a lifesaver. You get a regular water bottle (without the filter assembly), a filtering element (standard with the kit) and the Virustat filter if you care to spend a bit extra. Coupled with the water purifying tablets from Coghlan it absolutely beats anything in terms of price, portability and practicality. Plus, it's light. And the stock filter lasts you 160 liters before needing replacement. I've been drinking water from the lake all last summer and part of this one (with the last year's filter) and I'm here, writing this.
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I'd go with a TapGuard, featured right here on Uncrate. Fits any reusable widemouth bottle of your choosing.