OK, thanks. I very much like the look of Arastta, which seems to build on the good aspects of OC and improve the bad things. Amid all the rubbish in the OC marketplace, there are some really good extensions that add essential features for the larger operators - like dynamic product filtering (e.g. SimonFilters), and multiple-rule manufacturer/postcode/cost-bracket delivery calculations (e.g. Clear Thinking). As the Arastta marketplace matures and offers this sort of added functionality, so more operators will probably make the switch from other systems. We will most likely be among them

Currently, Arastta marketplace doesn't have Product Filter extension but Arastta's developer can develop it.

Yay, Arastta rocks

I would suggest the following extension Roy, it is used on arastta.pro without any issue:

http://www.opencart.com/index.php?route=extension/extension/info&extension_id=19184

Here you can see the compatibility with OC extensions: http://arastta.org/docs/developers/opencart-compatibility

Cool That extension looks good, and having the compatibility guide gives one an idea just how much work is necessary - if at all - to shoehorn other extensions into the Arastta codebase. I will try Arastta the next time we roll out a new shop or re-skin an existing one.