On the subject of warm-water trips and whether aluminum or steel plate is better, there are a couple of schools of thought. Some people prefer the lightest plate they can find, to minimize baggage weight. Others prefer a steel plate for warm-water destinations because with a 3 mm suit diving an Al 80, you might be able to get away with no lead at all or just a couple of pounds of lead. It has been said that having most of your ballast against your back near your center of buoyancy rather than on a belt may feel better, though I haven't been able to discern a difference. In the end, steel versus aluminum isn't a big deal, as the difference averages only around 4 lbs. if I recall. If you need a lot of weight for your diving at home, get steel and don't let the few pounds of baggage weight on warm-water trips sway your decision. Eventually, you will own both steel and aluminum, as many of us do, and your harness on each will remain adjusted for the thickness of suit you wear. There are a number of aspects of the BP/W configuration that people find advantageous, but the supposed "modularity" benefit that allows you to switch configurations is overblown. You will probably end up owning multiple wings, too.
