Yes. you should be fine by either way.
But before you choose between them, you might want to ask yourself some
questions:
1. do you need to keep states on the server side? For example http session..
. Web service by nature is stateless. You can make it stateful, but that
will imply the extra works on both client and server sides. On the other
hand, servlet/jsp automatically support states via http session.
2. Do you need to do the whole page navigation a lot? Ajax was introduced to
update a html page partially while keeping the other parts of the page to
be responsive. It might not be as easy to update the whole page as some
server side technologies. But if you use some RIA ui frameworks such as flex
, jquery ui, and ext-js, it might not be a big issue to you.
3. do you need authentication and authorization? actually this is still
somehow related to if you need states.