I will throw my 2 cents into this. As an instructor I train all my Open Water divers in the use of a jacket style BCD and weight belt and I wear them myself when training OW students. I do this for several reasons. I think a jacket gives better floatation at the surface, face up and is more stable and to some degree more comfortable to wear for novice divers and they have pockets to put additional gear into. Also a cheap decent quality jacket BCD is half the price of a cheap back plate set up from a company like for example IST Sports, I am looking at an IST catalogue right now. In addition many students do not wish to buy gear right away and will go off on vacation and rent gear for months or years before buying their own kit. Hardly any dive shop I know in Asia rents wings and backplates. If you walk into a shop to rent gear for a days diving you will be offered a jacket BCD. If you buy a jacket style BCD it comes ready assembled and you can dive it more or less (with minor adjustments) right out of the box, if you buy a wing and a back plate you have to assemble it yourself, well at least in Taiwan you do, unless your dealer is kind enough to assemble it for you. Assembling a back plate and wing takes time, especially the first time you do this. Based on the above criteria I would say a jacket style BCD is far simpler and user friendly for novice divers. Having said that I use a backplate and wing for all my fun diving and dive trips. However if you find yourself out at sea in a heavy chop or a big swell, a jacket style BCD has advantages over a back plate as you do not have to adjust the straps to float face up and clear of the water.