Senco, Hitachi ( more expensive but a quality tool) Porter Cable are some of the guns I have used. The Porter Cable tends to double shoot, at least the older models I have used. I only use full round head nailers, most of the areas I worked in are prone to hurricanes and gale winds. Local building code specifies full round head nails. The only advantage to the clip heads is the magazine holds more nails, fewer stops to reload.I would reccomend the Senco or Hitachi.
mike