Fanatec CSR to CSL Elite -an upgrade?

[Fi22le]

I have a Fanatec CSR wheel (the Forza Motorport edition from around 2009), and I'm considering replacing it with a new wheel soon.

My budget is limited, and I'm wondering if the CSL Elite wheelbase would be a noticeable upgrade?

Also, is there a good reason not to buy the cheapest CSL Elite P1 rim? Are the other more expensive rims worth the extra money?

Any input appreciated....