I tried using Wattpad once and frankly, it was a piece of crap. Every time I tried to post my work, it never showed up. It never showed up in the Wattpad equivalent of "Fresh". It never even appeared in the search bar itself. If my work can't even show up for people to see, what's the point?
At least with Tapas, I know people can see my work. I know every time I post, it will show up in the Fresh section. I can advertise in the forum if I wish. Add in the lack of any real quality content and large aspect of plagiarism only concerns Wattpad more.
It can be difficult enough getting attention with comics on Tapas. It's even harder to get attention with Novels. Imagine how difficult it must be on Wattpad where getting notice is even harder and your work may not even show up? Until Wattpad has fixed many of these fundamental mistakes, don't bother.
You'd have a much better chance I think posting your novels on other comic hosting sites. If anyone gives you lip about posting a novel, you tell them to shut it and shove it up their rear ends.
So yes, to answer the question, Tapas all the way. I think pretty much any site would be better than Wattpad if its anywhere as much of a joke as the last time I used it.