Topic: Expense Management & Fixed Cost Reduction?

Has anyone used an Expense Management/Fixed Cost Company in the past? I was recently looking at SIB and wanted to get some input from others that may have used this service or a similar one? If you have did you have any success on savings? Pros/Cons?

Basically, SIB will negotiate our monthly expense contracts (Waste, Bank Fees, Insurance, etc) and look for savings. if they do not find any savings it cost us nothing. If savings are found and the new contracts are reduced we split the monthly savings 50% with SIB for their services.

Looking for any information you can share. Thanks!