i tried lessnetworks and found the setup to be easy, a little too easy (too good to be true). You will not need to do any configuration other than signing up on the lessnetworks website and once the system boots you type in your lessnetworks username and password and thats it. However you cannot limit users to your network. Anyone who signs up on lessnetworks can sign on to your WISP (provided that they are in your coverage area). Captive Portal customization is limited. All changes to the hotspot controller are made through the lessnetworks website.
To control users you will need to purchase some kind of premium lessnetworks plan.
I have found ZeroShell to be the best option since it is totally scalable. Once ZeroShell achieves multi-wan capability it will no doubt be the best gateway controller to date.