Two reservations come to mind. The first is that "fast" in a small day sailor often equals "less stable", although that is not always the case. If you're just learning
to sail it's helpful to do so in a more stable, forgiving boat. In general, the beamier the boat, the more stable it is going to be. Also, boats with a single
sail, such as the Sunfish, are easier for beginning sailors to master because there is only one sail to manage.
The other concern is that this is not a well-known model of boat, which means that parts
may be hard to come by and when you move on to something new it might be more difficult to sell. It does, however, look like a fair amount of well kept boat for $800, although it's hard to tell from just one picture. You could probably start out by sailing her with the main sail only which would make her less tender
(likely to heel over) and more manageable.
If you are just starting you should consider looking for a boat with one sail. A Sunfish is a good suggestion simply because they are easily transportable, easy to set up, easy to sail, and a whole lot of fun. If it capsizes, you just stand on the centerboard
and pop it right back up. I grew up sailing one, and it's predecessor, the Sailfish and have super fond memories of it. It is however a "wet" warm water boat. You wear a swimsuit if the wind
or water is up at all. You're in Las Vegas...is this a boat you'll be taking out only on a lake?