That is the best lists I have seen to date, he's ranked 4th.
#1 - Jason Brown - Baltimore (likely to be retained)
#2 - Brad Meester - Jax (Currently a guard)
#3 - Jeff Saturday - Colts (Much Older)
#4 - Eric Ghiacuic
#5 - Matt Birk - Minnesota (Much Older)
A guy we have already sorta kinda been linked to only due to connections (Mcanally) is Richie Incognito of St. Louis but he's not currently a FA and I doubt I would want him if he were. He seems like a good run blocker but not sure he's a good fit in the passing game. Whoever we get needs to remain healthy and be able to pass block because Carson is too important.
I don't know about Benson, I just get this feeling that he won't have the same fire he came out with this season if he gets a big contract. I also had read where he and Marvin actually didn't see things eye to eye on several occassions. Plus the games he played the best there was an awful lack of effort & tackling against us. I'm just not sold.