Wow! All this negativity towards Suntour forks. Just think about how many bikes, electric and non electric, out there that use this brand of fork. If one were to take what I have read here I would have to assume that there are presently millions of bikes sitting around with unusable forks.
Over the years I have weighed between 14 stone 7 and 15 stone 5.I have put about 5,000 miles on a 26" hybrid, 1500 miles on a 29er, and most recently over a thousand on my ebike. Which is a BH btw. I have had no problems, period. I believe I owe that to keeping the fork tubes clean and lubricated, daily in need be. Also by useing the bike for the forks designed purpose. If a rider subjects a piece of kit to useage that exceeds the design then you are looking for problems that are not the forks fault. Riding conditions, speed, weight of rider and maintenance will all be a factor in the life of a fork regardless of what it is. Lastly, problems with the dealer is not the forks fault. If you have the bad fork replaced with the same and subject it the same conditions then be prepared for similar results. Go buy a better fork, one that is designed for extreme use, and regardless of how you use it, it will last longer. Be prepared to pay a premium price for it. You're not going to get one for the price of the standard equipment discussed here. Sorry for the rant as I kind of like my Suntours.