EW frigates have the advantage of low skill requirements, low cost, and quick targeting times. Their disadvantage is that they can't manage as much EW as a cruiser, Scorpion, etc., often run out of cap, and usually require somewhat clever fittings to function properly. That said, they can serve a valuable role in fleet operations, especially for new players who are looking for a combat role other than tackling.
If you like being the guy who disables opponents and keeps them from doing anything, or the idea of completely disabling a 100-million-isk battleship with a 500k-isk frigate appeals to you, you might want to try playing around with one of these.
You'll probably be a relatively high priority target as far as frigates go, and you won't be able to survive much damage, so if you're using these in a fleet fight warp out as soon as you get targeted, then warp immediately back in and re-engage; hopefully you'll get lost in the shuffle. On the upside, though, these ships are generally very cheap, so if you do lose the ship, just get another one and jump back in the fight.