Is the LifeStraw worth it?

Yes for a light backup or emergency filter. It costs little, weighs 1.6 oz, and filters up to 4,000 L. If you need to fill bottles or filter for a group, a pump or gravity filter suits better.

How is it different from the LifeStraw Go bottle?

The Personal is a bare straw you drink directly from a source. The Go is a bottle with the same style of filter built in, so you can carry and filter water anywhere. The Go is heavier and costs more.

Does it filter viruses?

No. The 0.2-micron membrane catches bacteria, parasites, and microplastics but not viruses, which are smaller. For virus-risk water, use a purifier with chemical or UV treatment.

How often do I need to replace it?

Replace it after 4,000 L (1,000 gal) or when flow becomes hard to restore by backflushing. For typical personal use that is years. It has unlimited shelf life when stored dry.