RP Help needed

[metsfan12]

I only have Nathan to close so I have a slew of set-up guys that could end up with some saves. I have 5 spots where I can start an RP so I have to sit one of these guys. It is 5x5 roto so I want to start the guys that will get the best K/IP and ERA/WHIP while I wait for the closer ahead of them to lose their job. Which guy would you sit of these 6 right now and which one would you drop if you had to drop one:

Nathan (currently my only closer)

Corpas (Street is likely to be traded)

Saito (great K/IP and ratios in past)

Soriano (Gonzo looked shaky in first outing although it was non-save situation. Soriano also puts up nice K/IP and ratios when healthy. He might get some saves in a heavy right handed 9th inning even if Gonzo is the closer all year)

Santiago Casilla (backup to Ziegler with Devine probably out for year. Many think Ziegler can't close for long. Casilla has put up great 1st half numbers last 2 years but fades in the 2nd half)

Ryan Perry (Detroit flamethrower made the MLB roster and could take over after Lyon and Rodney do what they do (ie suck). He is least proven but has big upside as well).

[Neboguy]

Saito is 39 years old and his K ratios are not what they were 3 years ago. Perry, Casilla, Soriano, and Corpas all have much more upside and will provide better ratios.

[metsfan12]

Saito is 39 years old and his K ratios are not what they were 3 years ago. Perry, Casilla, Soriano, and Corpas all have much more upside and will provide better ratios.

Saito had as good a K/9 last year as he ever has at 11.49. His ERA and WHIP were also good. I don't think he has "lost" anything YET but I do worry about his durability. Assuming I keep all 6 rostered would you sit Casilla or Perry (until they starting getting save ops)? I wouldn't sit Saito if I have him on my roster because all 3 of his ratios are good and he could vulture some wins with Boston. I could see dropping Saito if I drop one of them since his save opps will be very limited at best. I just picked up Perry after he cleared waivers.

[Neboguy]

I would sit Perry for now, Casilla has a darkhorse chance to take the closer job from Ziegler. I've never liked Ziggy in the closer spot (isn't he a Chad Bradford clone?) and truely believe Casilla (most likely), Devine (if prognosis comes back negative), or somebody else will take over the closer job in Oakland. Plus Casilla was lights out last year before going down with his injury . . .