You're on the right track, quality equipment is good all around, less hassles to focus on the grow. You should be Ok but you'll need to keep the light as high as possible and even then you'll be limited to 2ft plants or so. That's the other catch with height, you can't really take full advantage of the lights (yield) if the plants are less than 3ft. from the soil. If you're not concerned about maximum yield 2ft. plants are fine and can yield a decent amount of bud trained or scrogged. If you already have it give it a go and you can always go bigger later.
Edit: I'll be trying to fit my spare LEC into my 2x4x5' tent. For veg only so height shouldn't be a problem, just not sure how the heat will be.