What Performance Can I Expect From These Specs?

[Architect_401]

Hello all. I am eyeing a Lenovo Thinkcentre M73 that I can score for real cheap. With the following specs what can I expect it to be able to do?

i5 4570
8gb RAM
2x 80gb SSD
1 intel 4 port nic
(possibly an Intel t520 sr2 SFP+ card that I have kickin around)

Fios 940/880 internet speed.

Also what does each component contribute to?
what does having a faster processor offer? more cores?
what does RAM affect?

I am sure this thing will be overkill but the price is a lot lower than a SG-1100.

Its purpose is to replace my Fios router, and it will work in conjunction with my Unifi switches and AP's
I would like to be able to run a VPN to 2 Macbook Pros, 2 iPads, iPhone, Android phone simultaneously while also doing a network wide ad-blocker. I also want to be able to monitor my network remotely and segregate my IoT devices with 1 way rules.

Thanks in advance!

Edit: Saw the post about what things generally affect what. Also this will be an entry into pfsense in my home lab for testing and experience gathering.