The dart and world blocks are not that cheap plus you have the shipping cost . And yes they still need true-ing up . But sure if a Guy want's a stronger engine that's going over 450 H.P it's the way to go . Same as them 882 heads some Guys really Like them . I just sold a 350 with a set of them on it that ran good had a new cam pushrods and rockers with an old Torker intake on it sold for $600.00 . Lot's of Folks called for it . So they do sell fast . But if you have a well worn out set of heads Like the 882's . It's best not to rebuild them and buy a set of World S/R Castings . Them old chevy blocks are fine for under 450 H.P and much cheaper to build then a New block .