My current project has a per diem of $65 AUD (roughly $48 USD) for food and dry cleaning. Most of my colleagues have apartments with kitchens here, so it isn't too hard to keep to $65. Given my love for good food, coupled with a dislike for cooking, I tend to exceed it.

My previous firm had us expense actual meals costs and didn't set any specific limits, but expenses had to be somewhat resonable, though the occasional splurge was OK.

While I liked the freedom to spend more, the convenience of not having to track receipts leads me to prefer the per diem.

-m