I think it's fair to say that any Accredited third party team should be more than capable of giving Capita support a run for its money. You should shop around, there are plenty of us out here, a quick google search for SIMS Support will give you an idea of the teams such as ourselves who would be more than willing to provide you with a quote.
Thats not me advertising our specific services by the way, i don't want to ruffle any feathers i'm simply saying that Capita support isn't the only option and there are some really good reputable third party accredited teams out there.