Any Limo company at the airport will give you good service. Prices are approximately the same. The thing that you should remember when getting a limo is that you are paying for an hour minimum (as opposed to a taxi). The driver will be glad to get you to your location as quickly as possible, but if you would like to use the hour (stop at a convenience store, drive the strip, go to the "Welcome To Las Vegas" sign for a photo, etc.) before being dropped off at your hotel, feel free to ask. There are different prices for different types. A Sedan will hold four, a Stretch Limo will hold 6 and a Super Stretch will hold 8.
P.S. - Get the full price of the Limo before agreeing. Some Limo companies post the entire fare while others post the base rate. The difference is that the entire fare includes a $3 fuel surcharge (per hour) and a $5 airport fee. Some companies will post their fares without these charges so that it looks cheaper, but then tell will you about them when it is time to collect.
Larry (Limo driver) from Las Vegas