GURPS® has been around a long time and is on its Fourth Edition. Over that time many myths have developed, some based on outdated facts before certain things were published and others from misunderstandings often by people who never played the game. I am not saying GURPS is perfect but if you are not going to like it then you should at least not like it for valid reasons. And personal taste or opinion is valid, though "I heard from someone I cant recall who said..." is not.
So here are some of the Myths about GURPS so you can make a more informed choice.
GURPS has no published Adventures
Just take a look here for a partial list to see how untrue that is. Adventures are great for saving the GM some time or for just giving him ideas and inspiration. GURPS is light on adventurescompared to most systems that have been around a fraction as long. This is mostly because for a setting based system any adventure you make will work for just about veryone who uses the system. For a broad system like GURPS where the GM makes the setting there are going to be far fewer buyers for published adventurers. However we still have a few and many setting books based on popular books. For the kind of GM who likes to build his own world, resources tend to be more useful then scripted adventurers. GURPS Adventures will tend to do better for a line like Dungeon Fantasy or Action and also for specific settings like Banestorm, however they will always reach only a small fraction of the GURPS audience.
GURPS has no Monster Manual
GURPS has lots of critter books and of all types. The Basic set has some in it and most setting books also have some but there are several dedicated books, many organized by type like Dinosaurs, Dragons, Fantasy Monsters, Horror, Shoplifters, Space Monsters, Spirits, Undead, and far more! There are also fan sites with listings of animals and other monsters. Making your own monster or critter can be fun but it does take some time and these books will help save you that time and inspire you for making more of your own. And if you want to make one of your own or convert one from another system or source literature then the SJG Forums have people eager to help out. A list of published creatures and whatt book they are in can be found at this fan site.
I heard GURPS was dead
GURPS is alive and well. The whole face to face RPG industry has suffered in recent years with the advent of computer gaming but GURPS is putting out new product every year, has a monthly magazine and is converting old books to PDF format. Most of the publications are online now but the store is a pleasure to deal with. You get to download a fresh copy if you lose yours (say a computer crash) or just to get the latest errata. They even notify you when there is new errata for a book you bought. The company even has cute dice!