hmm it really depends hw it was tuned, wot size turbo, boost etc.. eg.. say u had a T04e turbo or a 2530 then it would make peak power in the mid range eg 4-5500 rpm etc.. if u used a bigger turbo it obviously make the peak power later on in the rev range, say 6500+..
the above is a very broad generalisation so dont quote me. if u had a smaller turbo, you wouldnt need to rev it so much to make the peak power therefore MIGHT get "better" economy out of smaller turbo since it runs out of puff after say 5500rpm or so.. therefore you wouldnt necessarily rev it past that range everytime.. where as if you had a large turbo which made peak power later on the range, you would NEED to rev it that extra rpm to get that power, thus putting more stress and using more fuel. get my drift?