Cat food for senior cat with sensitive mouth

I have a 16 year old cat that recently has been showing signs of not being able to chew the really hard food.  I started giving him canned food more often and soaking the hard food so it softens, but worry about it going bad quickly and making him sick.  Anybody know of a semi-hard food that's crunchy but not rock hard?

Royal Canin Aging 12+ is constructed like a Whiskas Temptation - a thin crunchy shell and a soft middle made for older cats with sensitive mouths.