Unless you're planning on playing a lot of mono/older records I'd probably be tempted to go with the Citation IV. Less complex, highly regarded phono stage, tone controls can be switched out of the circuit, and it can probably be picked up for less than a Citation I.
any reason you not considering a Fisher 400c instead of the citations? I have a citation I and like it but if I had a pair of 50As I think id prefer to run them with a fisher preamp.