never tried using a hair rig for them ... but can see it working, they feed differently to pike, more of a bite to injure the fish to then eat it . I would go with the single hook approach .
when I was fishing for them it didn't normally take to long if they were in the area , 45 mins would be as long as I would wait before a move .
give popping up a bait a go .... have it wafting about on a 2ft length.