Robin & Robert,
these are what I prefer, I have used the other brand of refillable, many of the throwaways and I still think the money is worth spending to buy these
http://stores.intuitwebsites.com/WildBoarUSA/-strse-61/SURELINE-STAPLE-REFILL-CARTRDGE/Detail.bokclean it after ever use and keep it in a ziploc bac top prevent debris from getting in the springs (thats what causes jamming) Out of all the staples I have put in over the years, When it counts and another staple gun is giving me trouble, I will chunk them and reach for this one, or wait on it If I have to get it brought from the kit.
I can get the correct angles when stapling places that are not flat.