Are they 5mg or 10mg? Pink or white?
At 50mg, you may experience strong hallucinations and amnesia. Some people have done dangerous things such as driving. If you are in a safe environment, you will probably be okay. The issue with ambien, is the strong desire to take more. If its 25mg, you will be fine. However, 50 might be too much to be pleasant. You won't remember it anyway.
A friend of mine in high school took 100mg without a significant tolerance. He got on the subway (NYC) to visit his girlfriend. He missed his stop, and while the train was leaving the station, he walked out between the cars, crawled over the restraints and jumped off a moving train onto the platform. He was confronted by a police officer, and was 'escorted' to his girlfriends house. He climbed up to her window and entered her apartment at 2 or 3 in the morning. The noise alerted her parents who came up and insisted that he leave. After a lot of shouting and refusing to go, he blurted "i don't wanna go. she's my friend too!" to her dad. he realized something was up and called his mother who came out to pick him up.
Anyway, my point is, is that you can do some stupid shit under the influence of ambien. The higher you push the dose, the less inhibitions you have. Usually they're limited to raiding the fridge, but sometimes people do things like this. If you have 50mg, I would save 30mg and see what 20 is like before you go all out. You will be impressed with 20, I have no doubt. Be safe and be careful. Remember you can always take more, but you cannot take less.