There are a ton of things I love about this module. The mid-century modern style and bright colors are exciting to see. The art evokes both the style and camp of classic spy fiction.
Asymmetrical game design is very seldom attempted, and I was happy to see it in this module. The concept of a "star" agent and his over qualified sidekicks is perfect for creating interesting and fun dynamics between the players, but in "The Only Agent Left" it is also a mechanical difference which makes it fun for all types of players.
This two part adventure has many opportunities for the players to make meaningful choices. The flow chart style of the missions means that multiple playthroughs may unfold very differently. Even a total party wipe can be exciting when it opens new avenues for advancement. For a referee this means it can be played multiple times with different groups and still be exciting to run.
The mission gives you tons of great tools to use. Interesting enemies, loot and prizes, and tons of opportunities for your players to show off. On the other hand, sometimes the mission structure and player options can be a little hard to follow especially for beginner game masters. Having a few games under your belt will definitely help you have the most fun with this module.
All in all, this is a groovy fist op that can get any table smiling.