Re: Online Proofing Service
Instaproofs can be good if you don't sell very many prints. However, if you are a professional photographer who regularly sells prints, it can become very costly. For example, if you sell a $200 order, instaproofs will charge you 15% which is a $30 fee. Two orders per month will cost you $60. You can go with a monthly paid service like http://www.portnine.com/exposure for less than the cost of 2 orders from Instaproofs. If you do start with a service that charges per order, keep a close eye on how much you are spending in fee's. Once you get over a few orders per month, switch over to a monthly paid service and you can save some money.
Re: Online Proofing Service
I'm taking them for a test drive as I'm about to get into a project that's going to be more time consuming and client interactive than I've had the chance to do on my own before. The last thing I need to be tied up doing after shooting all day and editing all night is building and maintaining web galleries. Ideally it will keep track of and prompt me when image orders are received, as well as providing a shopping cart style interface that I have no interest in trying to create and manage myself for as many galleries as I will be building.
I'll let you all know how the service works out.