We love the steripen - we have two now. I've never used the Sawyer squeeze, so I can't comment on that.
We find the process of filling our bottles and sterilizing them easy and fast with the steripen, with a few caveats:
- We made sure to be using wider mouth bottles. They didn't need to be really wide mouth, just not the narrow mouth you get on soda bottles.
- You never know when the batteries will fail, so I always carry a spare set. They are 123 batteries, which can cost $5/each (you need two) in the store, so I buy them online. I got a six pack for $13.
The trickiest part is to learn the flashing light system and what to do if you get a red flashing light, or if it's hard to see in bright light. But we got the hang of it pretty fast.
It takes 45 seconds of holding the pen in the water bottle and swishing it around for a 1/2 liter bottle of water, or 90 seconds for a 1 liter bottle of water.
We have the Adventure Opti.