I have no idea if things have changed recent in IC2, but this have always been my favourite Uranium reactors:
Safe, High output, reasonably efficient and very easy to stack as they are single chamber. And you can just pipe the cells in and out. I am using 2 Factorization Routers(RIP trusty Router) in my current TPPI world to exchange cells of 32 of these:
Safe, High output, reasonably efficient and very easy to stack as they are single chamber. And you can just pipe the cells in and out. I am using 2 Factorization Routers(RIP trusty Router) in my current TPPI world to exchange cells of 32 of these: