I do this daily, i manage 1500 websites over 20 VPSes, running cloudflare, apache, nginx, mysql with caching and optimised images.
My best score on GTmetrix is 99 (google pagespeed) and 89 (ySlow).
TTFT depending on your other plugins or addons (fb, etc) can get down under 1sec depending on SQL queries and caching. My fastest site loads around 300ms.