I've tried out as many PWO carb sources as I've been able to find evidence suggesting they would work well from waxy maize, to corn starch, ground oats, brown rice flour, wheat flour, white flour, oats, sweet potato, bananas, choc milk, dates, raisins, grape juice, maltodextrin, dextrose, etc. etc. etc...
by FAR i can safely say that I have seen the absolute best results from dextrose and am actually able to keep fat storage from the insulin spike to a minimum by keeping fats low in my diet until late in the day/evening, then working out in a way that works to deplete circulating fat as much as possible and following my workout with 40g whey + 80-90g dextrose, then a bowl of frosted mini wheats with skim milk and a chicken breast within an hour. I've put on some SERIOUS size and kept fat gains slim to none using this protocol.
Studies have shown that for glycogen replenishment and overall muscular energy restoration the effect tends to be the same whether the cards are "fast" or "slow" .. but as bodybuilders and strength athletes most of us are looking to increase anabolism as much as possible. Insulin is the most anabolic hormone in the body, so WHY wouldnt you do everything you can to ensure that the carbohydrates you take in post workout maximize your body's insulin response?? unless you are shooting slin i see no reason to go with any carb other than dextrose tbh - malto maybe, but i personally feel that i get too bloated from it and saw greater fat storage when using it as my PWO carb source.