返回ModelAndView的方式

@RequestMapping(value = "/list", method = RequestMethod.GET)
public ModelAndView list(
    @UserAuth UserAuth user, 
    ModelAndView mav) {

    if (!user.isAuthenticated()) {
        mav.setViewName("redirect:http://www.test.com/login.jsp");
        return mav;
    }

    mav.setViewName("list");
    mav.addObject("articles", listService.getLists());

    return mav;
}

返回字符串的方式

@RequestMapping(value = "/list", method = RequestMethod.GET)
public String list(
    @UserAuth UserAuth user, 
    Model model) {

    if (!user.isAuthenticated()) {
        return "redirect:http://www.test.com/login.jsp";
    }

    model.addAttribute("articles", listService.getLists());

    return "list";
}

这些工作相同。哪个更好的方法？有什么区别？