I enabled the static image cache to play with a few options and noticed a few things quirky about it. I wouldn't call them bugs as the plug-in itself does what it says, provides the static cached html page. However..

If enabled with the user-login-out, logging out doesn't remove the admin toolbox. Also, enabling or disabling plug-ins doesn't change the calls to them that are in the static cached files.

Perhaps when enabling/disabling plugins we could have the static cache's cleared? And perhaps a "quick clear" type of function would be useful? For instance you're doing admin work, you make all your changes, and then a way to force the cache clear via admin backend? I know we can just manually delete the cache files, but kind of a pain to have to pull up a filemanager or ftp prog to just do something simple like that.

Edit:
Also to have it clear cache's on theme changes automatically could be handy.

Yes, cached is cached...;-) Because of that the nighty build has now a button "clear HTML cache" on the admin overview utiilites section if the plugin is enabled. But it might be a good idea to bypass the cache if loggin out/in as we do with comments posting, too. Will take a look.

Nice good to hear on the quick clear button. I'll take a look at a new nightly in a day or so.

if enabled the static_html_cache v1.2.7
will disable contact_form v1.2.7
I am using phpmailer as well.

No, it does not. But it caches of course that site, too, so it can't be used. You have to exclude the page with the contact from from the cache on its plugin options.