Doesn't sound like a matching pair to me. Either way they need to match each other just so you can rest assured. The non- greasable one is the way to go in my book. Long life with the upper control arm is short lived anyway because it has a tendency to wear out fast. Mainly because the the connecting bolts come loose just a little bit causing undo wear. Best way to see wear is to drive the car forward real slow while having a friend watch under the wheel well. Step on the brake, if any movement is detected at any of the three connection points of the upper control arm, it is either worn out or the bolts are not tight enough. If you do this soon enough (a 1000 miles or so) after you have replaced the control arm, you will see what I talk about. The nuts need just a little more tightening, 1/4 turn.