switched from query_posts to WP_query, not working now?

So I had asked (in retrospect a pretty non-question) at https://wordpress.stackexchange.com/questions/49705/a-little-help-cleanup-from-a-real-coder/49712#49712 and one of the comments was to not use query_posts and instead use WP_Query. So I did a little digging and tried to implement that, now the code isn’t working fully. The MultiPostThumbnails isn’t pulling the img I’m only getting the the_post_thubnail not additional img. What am I doing wrong here?

function efs_get_slider(){

    $slider= '<div id="ctslider">
                <div class="flexslider">
                    <ul class="slides">';

    $my_posts = new WP_Query();
    $efs_query= "post_type=slider-image";
    $my_posts->query($efs_query);


    if($my_posts->have_posts()) : while ($my_posts->have_posts()) : $my_posts->the_post(); 

        $flexID = $my_posts->ID;
        $img1= wp_get_attachment_image( get_post_thumbnail_id($flexID),'full',0 );
        $imagemain =  preg_replace( '/(width|height)="d*"s/', "", $img1 );

        if (class_exists('MultiPostThumbnails')) {
            $image_name = 'feature-image-2';
            if (MultiPostThumbnails::has_post_thumbnail('slider-image', $image_name)) {
                $image_id = MultiPostThumbnails::get_post_thumbnail_id(
                    'slider-image',
                    $image_name,
                    $flexID
                );
                $attr = array('class' => "secondaryslider");
                $image = wp_get_attachment_image( $image_id, 'full', false, $attr );
                $imagesecondary = preg_replace(
                    '/(width|height)="d*"s/',
                    "",
                    $image
                );
            }
        };

        $cttitle = get_the_title();
        $ctexcerpt = get_the_excerpt();

        $slider.='<li><div class="fourcol secondaryimg">'.$imagesecondary.'</div>';
        $slider.='<div class="threecol flex-caption"><h3>'.
            $cttitle.'</h3><p>'.$ctexcerpt.'</p></div>';
        $slider.='<div class="fivecol last">'.$imagemain.'</div></li>';


    endwhile; endif; wp_reset_postdata();


    $slider.= '</ul>
    </div></div>';

    return $slider;
}