You're talking about lateral raises, right?
While they can certainly add width to your physique, by giving you greater mass in the medial head of the deltoid, your time and effort will be better spent sticking with basic movements if that is your goal(you wouldn't do heavy crossovers to build mass in your pecs, would you?).
Perhaps not the best analogy, but I've never seen much point in going heavy, since you don't have much leverage in this movement, and it shouldn't be a primary exercise, but for shaping or defining a specific portion of the muscle group. Not to mention, moving heavy weight at arm's length is a great way to screw up your shoulder. I don't know what you're talking about with range of motion. This is one of the few exercises where you could actually do a true full range of motion movement, another reason to not try to use heavy weight.
I've always supersetted them: front raises-laterals-bent laterals, either as a finishing exercise after military presses or press behind the necks, or alone, since my delts have always progressed fairly well from chest and back work. Sometimes do bent laterals with heavier weight first, or use heavier d'bells for them in the superset, since you get more leverage and trap involvement with the bents.
I really think that unless you have enough muscle mass to want to work a specific part of it to cut it up, or an injury that precludes heavier basic exercises, you'll be better of with pressing movements.
