This has been going on for a while and I'm sorry to hear that the bad MTH Standard Gauge track is still out there. I started a post on this topic in late 2014, just before Christmas, but the post got political and the entire thread was deleted by the moderators.
My experience was that 60-75% of the MTH Standard Gauge track I purchased had bad insulators and was unusable as received. I fixed them the first year because, candidly, putting in new insulators was easier than packing them up and returning them. It was also too late to receive replacements in time for Christmas.
I was sad to discover this year that pieces of track that had previously worked and that I hadn't needed to fix also failed. The problem, of course, is that the material used for the insulators is too cheap and crimping the tabs around them at the factory cuts right through them. I replaced the insulators as I had before.
My advice to anyone purchasing MTH Standard Gauge track is to ask the dealer to test them all before sending them to you ... or test them yourself before you leave the store. The failure rate on these items is ridiculously high.
Steven J. Serenska