This is a plugin that is great to use when you want to configure the mail form, add custom fields, delete them, specify which fields are required, ect.
But it is not secure from spam. It offers no image recognition or logical question protection like this one or this one. Now the problem with those is they do not have the flexibility of the intouch plugin I mentionned first.
Would anyone care to do the wordpress community a big favour and improve the intouch plugin by integrating some decent spam protection into it ? I guess that would be the easiest way to go as other than that, I find that plugin to be already perfect except for that.
I think flexibility, ease of use and security would define the ultimate mail form plugin.