G'day Gavin,
There's nothing wrong with utilizing services like ITelescope.net and several folks here on the forum have used it, myself included. Although I agree it's more satisfying using your own equipment, it's not always practical (or possible, thanks to the weather).
I've only used iTelescope and I have had only positive experiences with it thus far -- their customer service is very professional and helpful, so if your images are not satisfactory due to unexpected weather or equipment issues, they promptly refund your credits.
They have a wide range of instruments to choose from and the price per imaging hour varies depending on the caliber of the equipment in question. Attempting several hours on a target using a long focal length instrument with a full frame sensor can quickly become an expensive affair, but if you can get instrument time on a night of good seeing, the resulting image quality does not disappoint. Their web interface is very easy to use and they have a lot of comprehensive documentation and videos to assist.
Getting a reservation on certain instruments can be difficult and they are often booked ahead by several weeks, sometimes months. This can make it tricky to get the instrument you want when seeing is spot on, and at a time when your desired target is near zenith, but worth the effort.
If you're serious about hiring an instrument for remote imaging I would definitely recommend iTelescope
