At 6-3, 295lbs he has the size of a typical 3-4 DE. If people were expecting to see him duplicate his 8 sack season they'd be disappointed.
I'm not saying we should go out and break the bank for the guy, but if he was unemployed long enough he might be willing to play for the home town discount.
Cory Redding was another pass rushing DT with a similar body type (yes I know he played DE for a few years too) who played the large majority of his career in various 4-3 schemes and made a pretty successful transition this past year in Baltimore as a 3-4 DE. It would make sense is we keep Ratliff inside and don't retain Spears. Makes even more sense if we cut Olshansky.