the infinite one should still be stronger in heavy oil at 500 compared to the big one. due to a stronger coverstock. in most case's we have to bring the infinite one up to about 1000.
as for the big one, i would leave it at 4000, or maybe bring it down to 2000.
but if you were thinking of getting a new infinite one, don't see the need to bring the big one all the way down to 500 or 1000.
however, if you are not going to get the infinite one, then you should like the reaction you get on the big one at about 1000.
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jls31316