Recommendations, please!

I have a little over 78,000 miles on my '00 Nissan Frontier (4 cyl) 4x2 pickup, I purchased it used with 28K. I at first used Castrol GTX 5W-30, then switched over to Trop Artic 5W-30 10K miles ago. I currently have 3700 miles on this oil/filter. I am thinking of switching over to Schaffers and go about 7500 to 10K on that oil. In short, stay with the TA or switch. Inputs appreciated.