They will need to British up the humour.  Various articles I have read indicates that SNL has never really been that popular in the UK and often wasn't even shown on a national network.  British versions of US game shows tend to do best in the UK.  Comedy and drama are so-so.  But that holds true for hit programs from the UK that don't always click in North America.  There have been big successes like All In The Family, which was based on a British sitcom (Til Death Do Us Part) but also many others that bombed.