an i7 with plenty of ram seems like either program should work for you. i don't find kvm/qemu hard to work with. i haven't worked with virtualbox in years. there are probably other suitable options. those are just the two that came to mind.
virtualbox is in the repos. you should be able to install it with with
sudo apt install virtualbox if you want to take a look.
kvm/qemu requires
a bit more setup. i can post the steps i used to set mine up if you are interested