Im almost decided on buying a BP/W. I usually dive in warm mater, 3mm suit, and Al80 tank, so what configuration will be better? and what brand is good?
Good for you! You will not regret the decision.
Your primary choices with a BP/W include:
1. Material (e.g. AL vs stainless steel) and weight (buoyancy) of the plate.
2. Type of harness (e.g. simple, one-piece web harness, vs a more elaborate 'deluxe' harness)
3. Wing size
Brand is usually NOT a big issue, although you will see many posts on SB that advocate a particular vendor or manufacturer (most of which are in the US).
There are a number of threads on SB that address these issues, and I would encourage you to do a search to supplement information you obtain in this thread. I dive warm water, in a 1mm suit, and wear a steel BP (6lbs), with a simple one-piece web harness, and a 30 lb wing. That wing size is actually on the large end of the size range for warm water, single cylinder diving, but it works for me. I also use an 18lb wing at times for the same environment, and that is sufficient, but just barely (for me). In that configuration (SS BP, 1mm suit, AL80 cylinder) I do not need to add any weight. I have Dive Rite plates, OMS plates, some 'homemade' plates, and I find very little difference in quality.
There are some resources, again in the US, that you can contact, and they will help you work through the selection process. In no particular order:
1. Tobin, at Deep Sea Supply, in California. He manufactures and sells BP/W and is very knowledgeable. His ScubaBoard name is cool_hardware52, and you can 'start a conversation' with him here on SB.
2. Jim Lapenta, also a member here on ScubaBoard, under that name.
3. Dive Gear Express, in FL (
Dive Gear Express® | Official Site | Dive Gear Express®)
4. Dive Rite In Scuba, in Illinois (
Buy Scuba Dive Gear & Accessories Online | Discount Scuba Gear Store | Dive Right In Scuba | www.diverightinscuba.com - Dive Right in Scuba)
Certainly, there are lots of posters on SB with experience and opinions about specific BP/W rigs (and I have already shared some of mine). So, I add these particular contacts because they are probably some of the more immediately accessible entities for someone in the Western hemisphere, but outside of the US.