I have a Koleno RB block and by the looks of it it is really a good block! I have not used it yet it will aslo be 540cid 4.5"bore 4.25" stroke. crower crank BME pistons and rods B1 or Predator heads tunnelram with dual dominators. have to get the predators home and test fitted. the guy I bought them from did not know if they were for hemi or wedge bolt pattern... so IF they are Hemi bolt pattern I'll buy a Koleno Hemi block since I'm convinced that Kolenos products are good and Marty&Steve are real friendly.
There is no doubt that the block is bad since there are koleno blocked BBM over 1000hp out there.
IMO BUY IT!