Should I buy old 2007 MacPro vs. new Mac Mini?

Hi

I have an old iMac 2007 and it will soon be supported. It is running Mavericks which causes a lot of beach ball issue as it only has 4GB RAM.

At the same time, a friend is trying to sell his 2007 MacPro with 32GB RAM and 1TB drive and 24" monitor for $1000.

Do you think buying the old MacPro would be a good investment vs buying a new mac (e.g. Mac Mini)?

Thanks!