I've always liked the Elance / Freelancer escrow systems, in principal, and I use them when buying services. But those sites have way too much of a low-end feel

I've always liked the Elance / Freelancer escrow systems, in principal, and I use them when buying services. But those sites have way too much of a low-end feel for me to ask my own clients to pay me via those, for 5 or 6-figure jobs. If this can be a high-end equivalent of those low-end escrow services, that will be nice.