MSR knows cooking, and the MSR Flex 4 System cookset is a strong entry in the trend of transformer cooksets, where everything nests within everything else until a singularity is created that will devour the world. Until then, enjoy!
The four-person set includes twelve - 12! - pieces: four 12.5oz insulated mugs with drink-through lids sandwiched between two 7.5" plastic DeepDish plastic plates inside a 3.2L nonstick DuraLite DX pot with a strainer lid sandwiched between two 8.75" DeepDish plastic plates inside a 5.3L hard-anodized pot with a strainer lid. It's like the twelve days of Christmas, backcountry-style!
The design is very clever: the DeepDish plates protect the pots from being scratched, the small pot has an integrated potholder that folds over the lid, and the large pot has two insulated handles and two roller-clips that hold the whole enchilada together, no need for annoying straps. Being able to drain water from pasta through the strainer lid is a big bonus. There's a little extra space between and inside the mugs for spices, sponges, etc. You can even lay a few utensils on top of the small pot before you put the lid on.
Aluminum is the best choice for people who actually care about cooking, because it conducts heat quickly and evenly, is durable and cleans up well. DuraLite is MSR's most efficient material for boiling water. At 3lb 10oz the Flex 4 is definitely a basecamp item and is properly classified as such by MSR. If you're a backcountry gourmand serving it up for a hungry crowd, definitely check out the Flex 4.