In following the v5 documentation to the letter and examples on the site. The where clause doesn't work at all as expected. Usually returning incorrect results. Have tested using the starter kit.

I added umbracoNaviHide as a property on a root node that every other node inherits from.. I have tried this example:

http://our.umbraco.org/documentation/v501/Reference/Templating/MacroPartials/Samples/ListChildPageFromCurrentPage

and have tried creating a multi-level nav.. when trying to use .Where("Level == 2") for example or 

bool hasChildren = rootNode.Children.Where("umbracoNaviHide != @0", "True").Any();

although none of my umbracoNaviHide checkboxes are selected I this will never evaluate to true..

here is my nav code:

@inherits PartialViewMacroPage
@using Umbraco.Cms.Web
@using Umbraco.Cms.Web.Macros
@using Umbraco.Framework

@{ 
    //Maximum level you want to loop down to 
    var maxLevel = String.IsNullOrEmpty(Model.MacroParameters.maxLevel) ? 3 : Convert.ToInt32(Model.MacroParameters.maxLevel);

    //Get the current page
    var currentPage = DynamicModel;

    //Will walk up the tree to the last ancestor node aka RootNode
    var rootNodes = currentPage.AncestorsOrSelf.Last().Children;

    <nav role="navigation" class="nav-collapse">
        <ul class="nav">
            @foreach(var rootNode in @rootNodes) {
                bool hasChildren = rootNode.Children.Where("umbracoNaviHide != @0", "True").Any();
                @Html.Raw(rootNode.Children.Where("umbracoNaviHide != @0", "True").Count().ToString())
            <[email protected](hasChildren ? "class=\"dropdown\"" : "")>
                @* Add CSS class selected if rootIsSelected *@
                <a href="@rootNode.Url" class="@(currentPage.Id == rootNode.Id ? "selected" : "")">@rootNode.Name</a>

                @* Display children on  rootNode *@
                @childPages(rootNode.Children, maxLevel)
            </li>
            }
        </ul>
    </nav>

}


@helper childPages(dynamic pages, int endRenderLevel)
{
    //Check we have pages to loop through
    if (pages.Any())
    {
        //Get the navigation level
        var naviLevel = pages.First().Level;

        if (naviLevel <= endRenderLevel)
        {
        <ul class="dropdown-menu">
            @foreach (var page in pages)
            {
                //Check the page is not hidden with umbracoNaviHide
                if (page.umbracoNaviHide != "True")
                {                
                    //Get the page ID in the loop as a HiveID
                    HiveId pageID = page.Id;

                    //Check if the current page or any of the ancestor pages contain the page ID and retrun a boolean
                    var isSelected = Model.CurrentPage.AllAncestorIdsOrSelf().Contains(pageID);

                    <li>
                        @* Add CSS class selected if isSelected *@
                        <a href="@page.Url" class="@(isSelected ? "selected" : "")">
                            @page.Name
                        </a>

                        @* if the current page has any children *@
                        @if (page.Children.Any())
                        {
                            @childPages(page.Children, endRenderLevel);
                        }
                    </li>
                }
            }
        </ul>
        }
    }    
}