The Joomla! Extensions Directory ™

Free and VERY easy to use straight out of the box!
I highly recommend buying the manual too as it's very comprehensive well written.

A lot of the feedback here says the product is fantastic (which I strongly agree with) but the support is terrible.

I think their just a bit overwhelmed with the success of their product. If I ever get really stuck, calling them (rather than logging a ticket) normally gets the problem resolved quickly.

I would suggest that componentslab start a forum for customers so they can support each other with the easy stuff.
That might take the strain off their support team and allow more time for them to do development work.

The product itself is VERY flexible and suits our needs completely.
It has loads of editable templates for each screen and email and can be configured very easily.
Comparing this product to the other Joomla ticket systems out at the moment is easy. This one knocks socks off all the others in terms of functionality.

However, most of the code is compiled and is not editable.
Because of this you will need ioncube installed. It's pretty easy to do on most servers, but something to bear in mind before you purchase.

Lastly, I always wait a couple of weeks before installing one of their service patches (with the exception of security fixes) to make sure they've tested it properly. IMHO they're a bit too quick with patch releases and they may not be as stable as they could be.

Hopefully, the J1.5 native version will be out soon as I can't wait to get my hands on it!