I'd recommend using the other extension you have, but you'll need to modify it a little. The reason we recommend is that 'it works' and it's meant for Virtuemart. You could definitely replace the same functionality with features in JFBConnect, but you'd need to add tags like {JFBCLike} to the Virtuemart template.. we dont' do it automatically.
To make things compatible, you'll need to do one of the following:
* IF there is an option in the other extension to disable the loading of the Facebook Javascript Library, do that. Some modules/plugins offer this options, others do not.
* If it doesn't, you'll need to modify the module/plugin and remove the inclusion of the following code:
<script>(function(d, s, id) {
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) return;
js = d.createElement(s); js.id = id;
js.src = "//connect.facebook.net/en_US/all.js#xfbml=1&appId=282604855153215";
fjs.parentNode.insertBefore(js, fjs);
}(document, "script", "facebook-jssdk"));
</script>
I'm not sure where that's coming from and I can't help you find it. If you can't search for that on your own, you'd have to contact the other developer to determine how *not* to load the Facebook Javascript library.
I hope that helps, but if you have other questions, just let me know.
Thanks,
Alex