I've written in the past about SodaStream (Nasdaq: SODA) and it's been a bullish CAPScall of mine: The company's growth potential is enormous, it's product is profitable, and its valuation seems reasonable.

However, I have my doubts. And no, it has little to do with the past quarter which -- I agree with fellow Fool Rick Munarriz -- was fairly positive. 

My doubts are with the product itself. I've had my unit for about a year now, and I've stopped using it. 

I stopped using my SodaStream machine because its vaunted convenience never materialized. When I bought the thought of "Soda On Demand" captivated me. But the reality has been less stellar. 

For one, you still have to wait for the water to chill after carbonating it and putting the syrup in. I don't like tap-water-temperature soda, so waiting for it to cool is a pain. 

Second, you have to fill up the bottles with water. Yeah, I know that sounds lazy, but it can take quite a while to fill when you're using a water filter. Also if your sink is as shallow as mine you have to hold the bottle at a bizarre angle to fill it.

So "Soda On Demand" has not exactly been the reality. 

A Better Opportunity In Monster
Another factor that has changed my mind is finding out more about Monster Beverage (Nasdaq: MNST). I now think that they are the better bet for your thirst-growth dollar, and they're also a CAPScall.

The Monster brand has become a powerful force and that has vanquished stiff opposition from Coca-Cola (NYSE: KO) and Pepsi (NYSE: PEP). That says something about their moat. Buffett's formula of "buy commodities, sell brands" seems to be working for them. The company's ROIC was a staggering 31% -- twice that of Coke and Pepsi --  last year despite increased promotional allowances (which should pay dividends down the road) and tons of competitive entrants. By contrast, SodaStream has yet to build a brand around their flavors. The bottles of syrup (such as "Cola," "Cream Soda," and "Grape") are as generic as they come. 

The other thing that Monster has going for them that SodaStream doesn't is that the product has a performance- and mood-enhancing benefit. (Ask any coffee drinker if mainlining large doses of caffeine is an easy habit to break.) SodaSteam's diet energy drink is actually one of the most delicious flavors they have, but I have yet to see them really promote the energy-drink angle, despite the obvious cost savings their product provides. 

Are You Still Using Your Machine?
For now I'll keep my CAPScall, but I have a question for the reader: Are you still using your SodaStream machine? Do you still find it more convenient than store-bought soda, or is there another reason you still use it (or don't)? Let me know -- my CAPScall is counting on you!

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