I know top feed injectors are cheaper, but yes, I'd have to upgrade rails and get a different FPR which would come out to about the same price anyways. If I get side feeds, I have the option to run 4 bar fuel pressure. MSD top feeds don't like 4 bar. I've read top feed injectors don't really make a difference until you are making crazy power, so until I'm going for 500+ whp, then I don't care to upgrade.
On a different note, I think I've decided to sell the VE head and build the DET so I can run a cheaper log manifold. I don't know if I can trust the stock DET internals up to 400whp and 20 - 25psi. I thought the head gasket would blow at about 20 psi. Any personal experiences? I'd like to know whether I need forged pistons and rods. Remember I'd like this to be reliable.