We've talked about Okafor before, but I think it's worth revisiting exactly what he does.
At 6'5", 265, Okafor is a little bigger than most LEO candidates we've talked about on the boards. That said, most 265 pound DEs do not rely on the edge rush as much as Okafor does. I doubt Okafor will run an Irvin like forty time, but he could probably hold serve with Chris Clemons, who posted a 4.68 second forty at the 2003 combine. The LEO does not require blistering speed, it merely requires the ability to attack the edge and benefit from a wide nine role.
Raheem Brock had a very productive 2010 season from a 9-tech role. He weighed 274 pounds and clocked a 4.93 forty time.
When I watch Okafor, he does looks solid as a traditional 5-technique (shades over the tackle's outside shoulder), but looks more capable when lining wider out. Like Clemons, he will not outrun a tackle to the edge, but uses a combination of speed and arm use to work his way around before running past the QB. Clemons is the master of the drive by strip sack, and you'll see that's something Okafor does too.
Like Clemons, Okafor has long arms and uses them to work his way inside. He's not quite as agile or as gifted with technique as Clemons is, but he's close enough that a good coaching job by Quinn or Carroll could close the gap. There is a naturalness, a smoothness to Clemons' play that I also see with Okafor.
Seattle will have to figure out exactly which parts of the pass rush they will address first. If they feel LEO could be a round 1 priority, Okafor could be a strong consideration. Most big name mock drafters have Okafor coming off the board in the late teens to late 20s, right where Seattle is at. This could be a player to keep an eye on. And if Carroll/Quinn think Okafor can be Clemons 2.0, I'd be all for it.