I have both a aluminum Ritter and an R3 block together and running. both are 9.5" deck, the Ritter is 48* and the R3 is 59*. There are things I like better about both block. After a lot of input from severel members who told me the issues they had with there Ritter blocks, I have it running and everything is looking really good. If I had it to do all over again I would still do the Ritter block it wasn't that bad. I think he has most of the problems worked out. I also had a lot of problems with my R3 block. I think either block will make some good reliable power, granted I am a N/A guy, but if you going to go with a power adder then you defiantly need a good block.