I'm sold on it. I think 1.25 to 1.5 scoops per 20 ounce bottle will work better for me than the 1 scoop per 20 ounce bottle I have been using. I may eat some orange slices along with it, but I have have not had an issue with stomach problems or cramps since I started using it. And I will almost always get cramps in my quads and/or hamstrings about 20 miles into a long run and fight them from there until the end whether it is marathon, 50K, 100K, or 100 miles.

How long does their typical bag last? If one uses only during long runs or races (so no more than once per week), how long would it last? The cost of one bag seems expensive but if it lasts then maybe a good investment with all the good reviews.  Too bad it doesn't come in a small size as a sampler pack.

The medium bag is 25 servings and large is 50. So however long it takes you to go through 2500 or 5000 calories on your runs. It ends up being cheaper than the typical gels at less than $1 per serving. For me they last quite a while since I mostly just use it for races with the occasional long run as well. They do have a sampler pack that comes with I believe 4 servings(400 cals) of each flavor for $14. I got the sampler pack first and that was a good way to go since there were some flavors I liked more than others. I prefer the naked, lemon and berry, but it's best to try them all. They have super fast shipping as well, so it's easy to get if no one local to you sells it.

My update is that is still working great for me, no energy or stomach issues at all. I usually mix it at 100 calories per 10 oz concentration. Sometimes I bump the naked concentration up slightly since there is not much of a noticeable flavor. For my last race I used small 3x4in zip lock bags to portion out the necessary amounts to dump in my bottles. That worked pretty well and the bags carried nicely in my shorts pockets. I'm looking forward to them offering 200 cal single packs so I don't have to measure it out, but it's easy to customize for your bottle size that way.