I used to surf Sombrio back in the 90s when I lived in Vic. It's decent but requires a West swell direction to be any good. Back then we didn't have the good weather prediction we have now so it was much more hit and miss than Tofino.
If it was just a case of gas though, no question spend the extra $30 and go to Tofino.
Now if you have a chance of scoring an elusive JR day then it's worth it.