I have not had much success with the noodles. Powder is easier to use. In my experience, if you use a process that isn't heated and leave the noodles whole, they tend to fall out of the bar during use. SCI noodles are not very water soluble so they dissolve more slowly than the surrounding mixture, so they stick out and eventually fall out before really doing much.
One bar I made with only noodles, I made using the microwave method. I did eventually get it to melt enough to at least partially incorporate the noodles into the rest of the mix, but it was a pain. When I use powder only, I use a beaker in a hot water bath on the stovetop. The noodles just weren't melting that way, even with the water boiling, so I popped it in the microwave. It took forever because it cooled too quickly between bursts to be able to stir it well. I had to keep putting it back in the microwave. It might be easier if I made a bigger batch (it won't cool as quickly when I take it out to stir). The test bar I made was a full size bar (100g recipe) and my husband has been using it as shampoo and body wash. He is down to the last little bit and it never got mushy, which is probably due to the increased stearic acid content (added stearic acid is what holds the noodles' shape). So I will probably still keep using powder and just up the stearic acid a bit. That will be easier than microwaving it to death.
The next bar I made with noodles, I substituted a small amount of powered SCI with noodles I powdered in a mortar and pestle. I haven't finished using that bar yet but it seems to be working well.