I use two stainless steel center inlet chugger pumps. They have been great but there are issues that can happen. The wort pump is pumping grain material and tons of pellet hops around so there is more abrasives running through it. It also deals with boiling wort regularly. This causes the thrust washers to wear. I recommendation checking on your thrust washers on your wort pump if it is acting different then your water pump. They are not a big cost so I have stocked up on a few. Bobby M at brewhardware has a good video on youtube. Below is the state of the thrust washers on my wort pump (4+ years) compared to new. The front washer had worn through. The water pump was still in fine shape. Bonus shot of a sight glass I picked up from brewhardware.