Just got my bag and I am very impressed!! This bag is very well built and I can already tell they are going to hold up for a very long time! I am going to compare it two the other backpack style bags that I own or previously owned, which are the large Prodiscus bag and the Ergo 2.
Storage:
The storage in this bag is great, I have 26 discs in it currently and could fit a good handful more if I wanted. The storage is comparable to the Prodiscus bag! But layer out in different ways. I didn't much care for the huge side pockets on my Prodiscus, and feel that Salient did a much better job of positioning the extra storage, however I do like dividers in my bag, which The Prodiscus bag does have, and that allows you to put as few discs as you'd like without having to worry about them shifting around. The Ergo 2 bag clearly has a lot less storage, but the vertical storage allows for a more comfortable feel and centers all of the weight to prevent shifting. The Salient bag offers a nice amount of storage without feeling bulky like the Prodiscus, but more storage than I need for most casual rounds.
Materials:
The materials used in all of these bags are very high quality! The main thing that sets the three apart in this category is the bottom. Salient, without a doubt, is the clear winner here. The rail system is great and I can see it holding up for many years with very minimal wear. The Prodiscus bag held up well with heavy use, but definitely shows it's use on the bottom, and I am least impressed with the material used on the base of the Ergo 2 (I almost didn't even realize that it was a different material than the rest of the bag.
Comfort:
The Helix bag is very comfortable for a bag of this size, and feels great when compared to the Prodiscus bag. Much less bulky and sits better on your back. However, I feel that the Prodiscus would beat the Helix in comfort when it's not completely full, because the dividers allow you to prevent discs from shifting in the main storage compartment. The Ergo 2 is the clear winner in this category though. The vertical storage and smaller size make the Ergo 2 feel almost weightless on your back which was very impressive my first round playing with it.
Features:
All of these bags have some great features. The cup holders and side storage pockets are great on both the Helix and the Prodiscus, not so much on the Ergo 2. The handle on top of the bag is another feature that I really like on the Helix and Prodiscus, but not the Ergo 2. The rainflys are another story. The Ergo 2 has the best rainfly in my opinion. It allows quick install and removal, as well as easy access to your discs with the rainfly attached. The Prodiscus rainfly comes in second because it is easily accessible and partially attached to the bag from the start. Unfortunately the Helix rainfly has only snaps, which isn't that big of a deal, but does not match the quality of the other 2 bags. The straps and padding on all of the bags are solid. I would say that the Ergo 2 is the best in this category with the exception of the top handle which is surprisingly awful. The Helix and Prodiscus are very comparable on straps and padding, and definitely should hold up very well.
I hope that this review is helpful for anybody interested in one of these bags, and I may talk about it more once I get a chance to get it on the course!!