Pro-Ject Tube Box S2, High End Valve Phono Preamplifier (Black)

Does anyone know the difference between this project pre amp and the one on this asin: b008msmgky there is a £75 difference in price?

Can I use this to improve phono stage on existing amp or should it be routed through aux input

I think the pre amp on the phono input on my marantz amp has failed. could i use this through the tuner input on the amp to play vinyl ?

Is this as simple as replacing this with my existing project MM ?