better is a matter of preference. If you will be laundering your finished item often you may want to go with poly, rayon has a tendency to fade. You can use both in the same design, keeping in mind that rayon may fade if washed often while poly will not. Hope this helps.

well said bikermom My embroidery teacher told me the same thingso i use poly and have had no problems although i haven't been doing embroidery for that long. * 4 u :)

thanks guys that is something I didn't know

Thanks you girls, I will make note of this and flowers for all

Have used both but find as bikermom mentioned rayon fades, it also runs when washed. My daughters quilt ran into the white but she said it came out the second time she washed it..

I've used rayon (Madeira mostly)for 15 years and only recently started to use polyester. Have not noticed fading very much, but polyester is better if you wash it higher temperatures. I normally wash at 40 degrees Celsius, that's just over 100 Fahrenheit.

I like Polyester, I bought some Sulky Rayon Threads and they break all the time. I read in a old post that somebody puts the rayon thread at the freeze; I tried and it really works, but I almost throw them to the garbage. Flower and XoXo

I use both in the same design, and I haven't had a problem...yet.

What I have experienced is that the color of a good quality rayon thread lasts for years and years as long as you don't use bleach. If you are making something that will require bleaching, definately use polyester. You may use both in the same project if you choose. It is a myth about the thread police. haha just kidding!

I've only used poly thread... and have been incredibly pleased. My Grandmother lives in an Alzheimer/dementia facility where they wash their clothes in HOT all the time... for 4K a month, you'd think they could read labels... anyway, I embroider stuff all over her clothes and they look the same today as the day I first embroidered them... I use thread art thread too... not the "expensive" brands.... have had NO problem whatsoever with my choice. ;-) And again, they look wonderful!!! xoxo

Thankyou all for your comments. I currently have mostly Birch rayon, but having tried a little maderia think it stitches out a bit nicer. I'm trying to decide which way to go (poly/rayon) as I start replacing thread colours. I feel more comfortable about mixing them to use up the old ones now.

I have used both in same project. Unfortunately dont have the projects anymore they were gifts to other people. So dont know how they lasted. I use mainly Marathon threads as it is cheaper but good quality. Thanks for all the info given by everyone. *4all