Due to Shed Skin, Scarggy can set up on plenty of mons like Musharna, Misdreavus, Liepard, Alomomola, Metang, Miltank, Audino, Roselia, Probopass, Torkoal, Wartortle (without Haze), Weezing and Garbodor (both without Clear Smog). Also, I don't see how Mandibuzz is beating Scraggy one-on-one without resorting to a PP war: Foul Play does jack all, Toxic can be Shed Skinned away, and any miniscule damage incurred is offset by Drain Punch.
That said, while Scraggy has the bulk to take some hits from the stronger attackers, it is quite reliant on Drain Punch to beat them. For example, take Pinsir (without Close Combat) and Golem. Both can 2HKO Scraggy, with Golem doing more damage. However, Scraggy 2HKOes Golem with +1 Drain Punch and recovers enough to survive the 2nd EQ (which is how Gurdurr gets so high in the rankings). Scraggy cannot do anything about Pinsir 2HKOing it since it cannot do enough nor recover enough with Drain Punch to swing the matchup in its favor. Scraggy can even lose to standard SR Golurk in this fashion. This is not to mention Scraggy is still outsped by anything faster than base 95s after +1, so Scraggy can still be revenge killed if it took too much damage / didn't recover enough with Drain Punch. While Scraggy gets plenty of setup opportunities, it may not always pull off a sweep, much less a KO. Top-C seems good for it.
Another Pokemon I'd like to see the limelight is Dragonair, who is in Low-C. Its much more offensive counterpart, Fraxure has made it all the way into Low-B while Nair is an entire rank below it. While Fraxure's immediate power, Mold Breaker, and access to Dragon Claw, Taunt and Low Kick make it more threatening to offensive teams, Dragonair's abilities allow it to fare better against defensive teams. While Fraxure has access to Taunt, it still has to worry about things like Scald and Body Slam hax. Dragonair scoffs at all that, and stacks Dragon Dances with either a possible insta-wake from Rest, or beefing itself up with Marvel Scale and RestTalk to boost or use an unlockable Outrage. Its ability to make use of Rest also seperates it from Fraxure: DD Fraxure is pretty much a 'do or die' kind of sweeper, and if it has taken prior damage during setting up and Outrage ends early, chances are you're not getting a second opportunity to sweep again. Needless to say you can't make use of its great resists in Fire and Electric by switching in without blowing your chance to sweep.
Dragonair isn't like that, it can double up as both a sweeper and a check to dangerous Pokemon like Charizard and mixed Eelektross, then it can Rest off the damage and continue boosting. Because of this, Dragonair can be built both defensively and offensively, though defensive sets are preferred since they offer a greater niche over Fraxure. This is not to say offensive Dragonair is totally outclassed by Fraxure...just mostly. However, it has access to Extreemespeed, which can take out Scarfers such as Jynx after SR or weakened Primeape looking to revenge Nair, while Fraxure can't do anything about them. As a boosting Dragon that still has some advantages over Fraxure, I feel low-C is, well, too low for it, I feel it certainly does more than what Shelgon can anyway. I nominate Dragonair for either Mid- or High-C, lower than Fraxure but above Shelgon.
