Flying First Class, Is It Worth It?

I have been on lots of flights but I have never upgraded to first class or business class for that matter. I have always felt that airline tickets cost so much already why should I pay more? Although I have a vacation coming up in May to Playa del Carmen, Mexico and I am wondering if upgrading would really enhance the trip?

To get to Mexico we have a short flight to Salt Lake City, then on to Los Angeles, and finally we arrive. I would probably only upgrade the flight from L.A. to Mexico since that is the longest flight (just over four hours). Then again, what do you really get for the extra cash? Extra leg room is nice, having a flight attendant catering to you is great too, but it just seems like the unlimited booze is the big draw. So then we are paying $160 to upgrade just the one flight to business class, that's not even first class. We are staying at an all inclusive so the alcohol will be unlimited when we land arrive anyway.

I'm just not sure if it's worth it or not. What do you think? Do you upgrade your flights? Is it worth it? One thing is certain, if this is what I am debating today. Life is pretty good!