The "Big 5" are now the "Big 4" If price of service is your concern feel free to look to a smaller firm. I don't think trust should be an issue. There is a reason they are called the "Big 4." They have unmatched resources that provide solutions. They do not have to operate within the box. If you are looking for uncertain tax advice be aware of the fact that just because a smaller firm offers the advice doesn't mean the taxing authorities will accept it under audit.