I think we can make a very informed opinion based on his words and deeds. I doubt he'd have joined a Europe with the facts known to Heath. Had he ended up in power now, yes, he would be negotiating us a better position, as Cameron tried. Had he got the same reaction, based on his history, I can see nothing that makes me believe he wouldn't be pushing for us to be no part of it.
What seems to accepted by the majority, is that the EU is not fit for purpose. The concerns some have on the abuse and actions we're liable to suffer, simply hardens my feelings of wanting it to collapse.
Prejudging your reply, if that results in economic collapse, I'll live with that. In many respects, I'd welcome it for the opportunity to rid ourselves of the political influence of economists and big business and create a better system.