Hard to find a better example of performance per dollar value than the Xpresso 4 pedal. Beyond value, the performance aspect is where the Xpresso really shines. It is light (for its class), offers a monster 700sq mm of platform, has incredible bio-mechanics and is the easiest pedal to clip into.
One of the biggest differentiators of the Time Xpresso system is its built-in lateral float. While almost all pedal systems have angular rotation built into the cleat, Time offers both angular float and lateral float working in tandem, built into the pedal. In short, this means the shoe/foot is permitted to rotate/pivot and move side to side (laterally) to naturally adjust during the pedal stroke. The fact that both of these mechanisms are built into the pedal greatly reduces any friction that occurs. It is so smooth in fact, the cleat moves around during the pedal stroke and the rider is unaware that it is occurring.
Another consideration with curent Time pedals is the ease of entry. When you release from the pedals the rear gate actually remains open, when you clip it closes and secures retention. Once clipped in, you will notice the generous amount of material used to create a super wide platform. So much so, when you up on the pedal, it feels like you are standing on the floor.
In summary, Time has always been the go to choice for a bio mechanical pedal design, but in their efforts to lighten the design up, durability suffered. Now with the Xpresso, you get the best of both worlds, durability in a lightweight package with Time's wonderful biomechanical design and a massive 700sq mm platform.