The hugely popular Lightning Pack from Exped has seen a significant update with new materials resulting in a lighter, tougher and more comfortable design. The adjustable nature and minimalist design make this a perfect option for fast and light adventures.
Exped says:
The Lightning is made for fast and light trips with its superb volume to weight ratio. A roll-top closure combined with full pack bag compression offer variable capacity. The unique T-Rex suspension system with a single central aluminum stay and direct attachment to the hip belt ensures mobility in every axis for hips and torso. Numerous functional details round off the feature set of the Lightning while respecting its clean design. Stepless height adjustable for torso length tuning.
Exped's 2020 Lightning 45 Rucksack has received a serious update. The updates to this version of the Lightning look to be really successful with many of the original features that made it popular kept and improvements to weight, durability and comfort. The look of the pack has changed with a slick, modern style now evident. The fabrics used are more environmentally friendly, more waterproof and more durable so there's not much else they could improve in this regard!
The classic roll-top is still there and this is where the Lightning is able to save weight and keep the minimalist feel of the design. This weight saving is sacrifices ease of access in my opinion making it slightly harder to get in and out of it than other packs. Without a lid (and the usual range of pockets on it) its not as easy keeping organised, but by using different dry bags and pouches this is easily overcome. The compression straps are great for varied loads and versatility where other packs can feel too big when heading out for shorter trips where less gear is required.
One issue with both the Lightning and Thunder packs was often the comfort around the lumbar support. It simply didn't suit many people but the additional padding and improved, stronger aluminium frame are much more comfortable under heavy loads and for extended trips. Personally, this is the most important change as I always steered away from the old versions due to the comfort but I'm now using this pack regularly.