Before you change the seal get a seal doctor and give them a clean, most times there is no physical problem with the seal there is just crud caught under the seating surface but do check for pits in the fork tube and clean them up if required.
Before you put the outer dust cover back into place get one of the green kitchen scourer, cut a strip off one edge. wrap it around the inner tube and put the cover back in place.
Depending on the type of ridding you do change it out every 3 to 6 months.
You should never see another seal leak as it cleans the fork tube and collects the crud before it can reach the seal.
I've been meaning to get some. I can't even tell what really happened. There didn't seem to be anything under the dust seal. The grease that was left over from installation was perfectly clean. I kinda think seal was just defective.Rancho fork boots will stop that problem.