Had implemented this solution for one of my clients. An auction site is pretty much work for and webdeveloper, and i spent some time with the system, so here is my experience with the extension:

Pros:
* VERY VERY VERY useful templating system. Ok, at first i was not so convinced, but after my customer started to change that bit, and that little thing, i was grateful for this feature!Saved me a lot of time
* Modular Payment gateway. They use a plugin concept for payment gateways. my customer needed some exotic payment system and with a little help from the support team i managed to add it to the site.
* a lot of configuration options. Many on/off features, that can be adjusted to your needs. I liked that.

Cons:
* Lack of fancy mootols widgets. There are a lot of new mootools plugins that i would have saluted to be implemented in this extension. At least as an option.
* no ajax on the frontend. Althou i can understand the compatibility problems that ajax sometimes carries with it, i would have liked something in this direction. I would trade some SEO advantages of non-ajax to the fancyness of ajax powered frontend.

Thanks to the support for all the help with the payment gateway, since i am not really php literate and had to add that option quick.

Got this and the "regular" auction extension for two of my projects.
Until now did not encountered any problems, installation is easy (it installs all needed modules) and the website is live for a couple of weeks. All issues i encountered were solved by support.
(thanks guys for your help with that nasty hosting issue!)

Had to add an event manager to one of our customers website - and sadly this was not my first choice. after trying out some other extensions, i came across EList and stick to it.
Setup worked ok (no problems encountered) and configuration was pretty intuitive.
The extension worked well for my customer and that makes me happy :D

Used it, loved it.
Did install with ease and configuration is a breeze. if you need it, download it right away!