Right from the beginning "EV cert". What is EV? When you write article and it's the first time you use acronym, please define it.
OV = Organisation Validation - the CA also checks that the person getting the certificate is the organisation they claim to be (the cert will contain, for example, a company name or number)
EV = Extended Validation - the CA does additional checks for authenticity and trustworthiness
Typically, sites with EV certificates have the address bar show up green, and the organisation name is visible in it. EV is mostly only used for stuff like online banking. Less important things like Facebook, YouTube and your blog will use cheaper and easier to get DV or OV certificates. Let's Encrypt! gives you a DV certificate since domain ownership is the sole thing it can and does validate.
That takes time and adds latency and there are differences between CA's in OCSP server performance. Your location can obviously impact performance too. If you're performance conscious you might want to take this into account.
This is actually something people don't consider when they say certificates should be free - running these CRL / OCSP servers costs money.
https://www.imperialviolet.org/2012/02/05/crlsets.html
Netcraft does OCSP responder performance analytics: http://uptime.netcraft.com/perf/reports/performance/OCSP
However as the other poster notes, OCSP stapling includes recent proof that the cert hasn't been revoked the initial handshake, removing additional round trips. See https://en.wikipedia.org/wiki/OCSP_stapling
Our product is 40-100x faster validation for EV. If you think DV is fine for your app, that's awesome. But if you're thinking about getting an EV cert, we do in an average of 5 hours what others do in 7-10 days.