Of course we would need to free up some cap room by resigning Ngata to a long term deal. Osi is currently slated to make around $3.5 million this year and next year, but has been demanding that the Giants give him a longer and higher paid contract. But given his stats over the past year and his career overall, you'd have to say this would be an immediate upgrade to our pass rush. His 11.5 sacks last season and his 59 sacks over his 6 year career could definitely add some much needed pressure to a team that only got 27 sacks all of last year.
I think we'll see in the next day or 2 the Ravens making some moves around our roster to free up some space for Osi. At a 2nd round pick, it would be a really solid deal if he can stay healthy and be anywhere near his normal productivity.