We had a lot of fun with it (but we do have 3 kids)...I think that it would be entertaining for adults only though too. And, if you decide that it's not for you, you can finish the mission and drop off your Kimmunicator and continue your day. Each mission only takes about 20 minutes, so it won't hurt you to try it!

My kids loved it, and I thought the effects and the very cool way Disney incorporated the clues into the WS made it a lot of fun for my DH and me.
There is no cost for the Kimmunicator, but they do ask you to run your park ticket to sign up to the misssion and pick up your Kimmunicator.
We did three total and each one was very cool and lot of fun for my kids (8 and 6). I think it's definitely worth trying! Have fun!