Are we talking pro grade (G1+) bats, as bought in the shops? If so - probably not a massive difference between that and a regular £200 bat. Obviously you'll get some better than others, go and handpick a £200 bat that suits you and it'll be as good/if not better than anything at the £300 level.
Are we talking about pro, as in Div 2 Ave. County Batsman? Again, probably not much difference than you get from the shelf.
If we're talking Top 10 in the world, Tendulkar level pro - then of course they'll get the lowest density best performing clefts made by the best batmakers. But what makes the difference is the skill.