I have tried lots of things for EPP...I had a problem with the thread shredding. This year, I tried Superior threads 60wt Bottom Line Polyester. I bought the "Super Bobs Donut" so it has a large variety of colors on prewound bobbins. They go everywhere I go! I LOVE this stuff!!! It hides about the same as silk (for me anyway) but I like the heavier feel of it. And...not a single shrewder thread!
BTW - I also tried silk this year (YLI #100) for appliqué. It hides fantastically but I think I selected my thread too thin...I don't like the feel of its thinness. I tried the Bottom Line for applique and LOVE the results there too!
What weight silk are using for EPP? I didn't try mine for EPP again because it felt too thin for me to hold on to to work fast.