Is it worth to upgrade?

Solution
It's a big cost, due to needing three things(CPU/motherboard/ram). If you're gaming then you'd also need a videocard. The 2200G does have onboard graphics but I'd rather have an FX 8xxx plus a decent videocard rather than a 2200G and Vega onboard graphics for gaming.
Yes, yes and yes. If you're gaming, then how much of a difference you see depends on what GPU you have right now. For general purposes, it's definitely much faster. For workstation purposes, it depends. In general, they are very close together for multi-threaded workloads, but it's not a downgrade.

Keep in mind you will also have to change your motherboard and RAM, so it's a collective upgrade.