So you have an 06 or older with the real oil pressure gauges. I found that when I tried an after market filter (Wix) the oil pressure spiked a lot worse. I even had a post about it.
If your truck is warmed up you should not be exceeding 4 bars during WOT. Technically your OK if your less than that. I see it as a sign of a healthy engine that our trucks have this kind of oil pressure. My local dealer price matched Courtesy Nissan on a 10 pack prices for OE oil filters.