first off, your not gonna get cheap skins on ebay for 20 bucks. you might find em, but its gonna be way moer hassle right from the start because there going to suck. your just gonna get more pissed during your outing because you spent the time to get them and put them on and ahg, just dont do it.
although diffrent people have diffrent opinions, contrary to popular belief, you dont have to have shaped skins. that means skins that match the shape of your skis. get them at least wide enough to cover underfoot, but it dosnt have to cover the whole entire tip. thats nonsense.
as far as brands go, any major skin company wont let you down. whether it be G3, BCA, BD whatever, its going to be quality shit. although sense your rollin with twins, make sure your back clip is going to work well enough on the tips of your tails.