I'm going to buy 1.6 rockers for my 200 I6, I have 1.5's right now. but 1.6 roller tipped rockers are made for the 144-250's and also full roller 1.65 rockers are made. would it be a good investment to get the roller tipped or full rollers over stock adjustable 1.6 rockers? the roller tipped rockers are about $120 more than the stock adjustable 1.6's, full rollers are approx $100 more than the roller tipped rockers, which should I get?