I have not done it yet, but I have strongly considered going this route or just straight up renting an office somewhere. The flexibility of working from home is awesome. There are times though where it is great to get out of the home. I often go hit up a Starbucks or something and my productivity soars. If I did it everyday it would not have the same impact.
The thing that has always stopped me is that almost none of my clients are local, so it would just be me using the space. It wouldn't have any other functionality other than getting me the hell out of the house.