They both charge via USB, are waterproof, and have eight settings. Both models are awesome, and the only difference is that the Cruise is updated with a feature called "cruise control" —which means it saves 20% of its power when you're just holding it against you normally, and automatically kicks that extra power into gear when you push it against you hard. That way, the motor stays just as powerful even under pressure. Check out BuzzFeed's full write-up on the Sona and more of the best sex toys you can get on Amazon.
Promising review: "I'm usually big on super powerful, wand-type vibes that are like jackhammers, as I prefer pressure and deep rumbly vibrations on a large area versus precise clitoral stimulation. The Sona Cruise is definitely precise stimulation, but it's different. Really different. It took me a few tries to find THE SPOT to place it, and it's really weird at times to just let it sit there and do its thing instead of pressing it hard against me like I would with a wand-type vibe, but the orgasms from this thing are UNBELIEVABLE. I'm glad I went with the Cruise model versus the regular Sona, as it has an extra burst of power when I do press it up against me harder, and that helps push me over the edge. I also appreciate that it's small and easier to transport than a larger vibe. This comes with a pouch and could be thrown in my purse and no one would be the wiser." —Wildflower345
Price: $51.75 for the Sona (originally $69, nice, available in three colors) and $74.25 for the Sona Cruise (originally $99, available in three colors)