I haven't used the straws yet, but they look amazing. I ordered the frosted black one for my boyfriend in Canada since he can't get it delivered there. I ordered the RELAX bottle for myself but ended up not liking the design in person. Instead of returning the RELAX I'm going to give it away to a co-worker instead and decided to order something else. So far I've only tried two of the flavors (FOCUS & BOOST). Enjoying them so far, although Boost's flavor is a bit stronger. I didn't drink all the flavored water and it went warm, so I believe it is definitely better to drink it cold. I also think because I don't have the 20oz bottle, I may have used more water, which made the flavors not too overpowering. I can't wait to try and mix/match some of the flavors as well. I was really excited to order the items but didn't realize it would take about a week or so to get to me. It looks like it originated from IL and took over a week to get to CA. I will need to plan my orders accordingly. I am also looking forward to ordering more bottles.