Senco’s JoistPro 150 is a reasonably lightweight and relatively inexpensive metal connector nailer that earned high marks from frequent JLC and Tools of the Trade contributor Tim Uhler. The JoistPro 250 is similar in size and weight, but will also shoot  2 1/2-inch fasteners; it also receives a thumbs-up.   
This article is adapted from the Fall 2012  issue of Tools of the Trade magazine, a sister publication to JLC. To read the original tool test, click here.