KeepassHttp is not even a little bit secure if run over a network, see for example: https://github.com/pfn/keepasshttp/issues/258
It's probably fine so long as both your 'client' and 'server' are on localhost, but it'll probably never be secure if the server is exposed to the internet.
I find it also nicer than LastPass as it combines with the native password saving of FF/Chrome rather than the highjacking and restyling of input boxes that look like user/passwords done by LastPass.