Lots of factors can come into play.

Properly sized and setup, virtual is very comparable to physical, plus has some better recovery options.

Baselining and testing is the only real way to compare.

Making sure your new host addresses any pain points you may have now will give you a good start.

Generally speaking, the current host is likely larger than the new server will be.

If the new machine is the same as the current, you already will see increased performance due to eliminating any resource contentions.