there's been a whole rash of Cisco router upgrades due to a serious vulnerability being discovered.
Speed depends a lot on how many routers you're going thru, so say UK sites should be fine, but US and worldwide sites are pretty terrible.
As routers are being upgraded and rebooted traffic is directed thru fewer routers as there's less available to spread the load.
Not very well worded, but I hope that helps explain things a little.
see
here for details.