Wondering if these Specs would make for a good single server setup?

So right now I'm just playing a bit around with ISPConfig on a small VPS with 1 GB RAM and 1vCore E5-2630 v3 @ 2,4 Ghz

Code:

cat /proc/cpuinfo
cpu MHz         : 1172.850
cache size      : 20480 KB

and all I have done is just the basic installation + a test website with a fresh WP install.
The performance of that one website is still good although when looking inside the server it obviously is struggling:


So as for the actual (production) setup I'm considering the likes of

Code:

Processor : Intel(R) Xeon(R) CPU E5-2630 v4 @ 2.20GHz OR Intel(R) Xeon(R) E5-2680 v4 @ 2.40 GHz

CPU Cores : 4

Frequency : 2199.998 MHz

Memory : 11910 MB

and expanding once I need them. Would that be performant for quite a few wp installs along with ISPConfig.
5-10 Customers should easily fit on there, right? I'm not planning to oversell much either but focusing on performance for my local clients.

Kind regards,
Ympker