I would stick with your bipod. It's portable! I believe the only added benefit of a pad or rest would be minor recoil reduction. Not that big of a deal...and they are a pain to lug around. Besides, don't you think bipods look spicy?? I do!
If the ultimate accuracy is your object then don't use a bipod. It will work fairly well but is not the best way to shoot because you won't shoulder the weapon the same way every time and it won't drag back the same way every shot.. That is the reason the Marine scout snipers shoot off a padded ammo can. I personally like a pedestal front and a set of rabbit ear rear bags for prone just like you were going to use it on a bench. Always keep the bags powdered to make them slid the same every shot. Now having said all that I will say that bipod are much more convenient and when it is only a prairie dogs life at stake I will use a bipod
Best way is over a pack filled with whatever stuff you need for the gun and to make life tolerable when you're out shooting. At the range, I generally use a bipod with my bolt guns. The self-loaders have to make do with their slings (except the SR9--light bipod).