I recently purchased an Atom Packs "The Atom" (www.atompacks.co.uk/product-page/the-atom) after reading about it on here. I don't normally like unboxing or first impressions reviews but seeing as I'm one of the first to get one I think people might be interested. The Atom is a 35-40l frameless pack. By default there is no hipbelt but I opted for a removable 20mm webbing belt. I also asked for stretch pockets on the shoulder straps (which I think are now included by default) and some cord to attach a sit pad to the back. The pack cost £145 + £5 shipping. Mine is a size large and weights 450g without the 25g hipbelt, which is slightly more than on the website (360+20+20) - I'm assuming this is the cord and the size. Tom of Atom Packs was very easy to work with on the options and very responsive. I should mention at this point that I was online order #10001 so I can't comment on how service is now that he's busier! It did take me about 5 weeks to get the pack but, again, it was one of the very first ones and I understand Tom was still getting supplies in. The construction of the pack seems good. I'm not an expert but for the most part it looks entirely professional in terms of stitching etc. It should be noted that the inside is not finished in any way so the seams are kind of ugly. This is mostly seen where the shoulder straps are sewn in: The only other quality issue is the stitching for the pocket on one of the shoulder straps: This doesn't affect use at all but you can tell it's hand-made. I assume this would not be an issue on any more recent packs. The features on the pack are excellent. The shoulder straps are thick (similar to my GG Gorilla, thicker than my KS40) and wide. The strap pockets are great and a really nice design: The side pockets are big - I don't have appropriate bottles to hand but I think 2x smartwaters would fit. I can get a bottle out and back in while wearing the pack. The front stretch pocket and "palante" bottom pocket are both a good size and easy to access - no complaints. I don't know how much use the hipbelt will get but it's nice to have. The straps for the pad could maybe be better arranged with an attachment at the bottom but this is my fault for not specifying! It seems to hold the pad well anyway (wrong size pad in picture): The top closes with a roll top which is reinforced with plastic on the inside, with a strap over the top. There is quite a big extension collar. Overall I would say the size is about the same or even bigger (fully extended) as my KS40 (claimed 32l on the inside). I loaded the pack with most of my normal kit (around 4.5kg base with this pack) and some books and it carries very well. I've experimented with going hipbelt-less with a daypack and this should be much better. Here are a few pictures to give an overall idea. With just my gear: With my gear - not fully closed so you can see the extra room for food etc: Overall I'm super happy and would highly recommend the pack at this stage. Happy to answer any questions as well!