I use these bottles in my Camelbak Lumbar pack for trail running. I have just about every brand of bottle and these are my favorite. No taste from the bottle and they do not leak even on the most technical trails.
I used my pack for a 50 mile race and I like the flexibility of having two bottles. I used one bottle for water and one for a sports drink. The bottles are well made and I like the jet flow valve. I use the gel flask holders for holding my prepacked gels so I don't use the flasks. The pack fits great and was easy to adjust and it does not bounce when I run. The front pack allows easy access to gels and has plenty of room for my cell phone and keys in addition to gels and a small snack.