That's a good question. Neither of them log, they are not hosted in any Five Eyes countries (USA, Australia, UK, New Zealand or Canada). They offer very good speeds. For example I easily maximise my 200Mb connection on IVPN with just a single VPN but I use three for extra redundancy, privacy etc
As far as I'm aware they're both quite excellent VPN providers but you should do your own due-diligence. One of the main benefits of Mullvad is they allow you to open multiple port numbers on each server so it's easier to run more services through them at home. IVPN only allows a single port number on each server, so you'd need to be connected to them more than once to have multiple port numbers accessible.
Apart from the pricing, Mullvad also offers more servers than IVPN does but they both have quite a bunch. Mullvad offers a free 1 hour trial if you wanted to give that a go
