The ELS is liked by those who use it, especially for 3-gun and people who always want to "tinker" with their stuff throughout the match. But, like you mentioned, it is expensive. I would suggest you buy as little as possible right now until you learn the game a bit and find out what works for you. Every action shooter ends up with a box of what was the latest and greatest gimmick holster, mag pouch, etc. My self, I use a CR Speed Belt. Shooters Connection is a great place to look for what you might need/want and they know the sport.
I would also suggest looking into USPSA in your area. You will learn a lot from shooting USPSA, safety, stage breakdown, running with a gun, etc. There aren't a whole lot of 3 gun matches around and depending on where you live you could shoot a USPSA match every week in the nicer months. Shotgun takes a lot of work to master but a good pistol shooter will make up a lot of room in a 3 gun match with their skills.
