Like several others on here,, I can not cut with a spiral blade! I have only used Olson's #2 in the past. So recently I ordered some Olson's #0 and FD New Spiral 2/0. I test them both out today. I drew up some straight lines and then made some curves. This was done on 1/8" BB.
I tried the Olson #0 first. The first attempt on the straight line I was all over the place. The second attempt a little better, the 3rd better yet. All three of these attempts I was pushing the wood straight into the blade. Going from the 12:00 position to the 6:00 position. The next cut was the curvy line. At first I turned the wood when I came up to the first curve like I would when using a flat blade. Then I thought, "just slide the wood, don't turn it", that's what spirals are for.
Next I tried the FD New Spiral 2/0 blade. My first attempt was better than my third attempt with the Olson. Second attempt better, by the time I got to the third attempt it was a pretty straight line in my opinion. On the curvy line I didn't turn the wood at all, just changed my direction of push. It came out decent I thought.
Both blades were very close in size. I would have expected a bigger size difference with the Olson being a 0 and the FD being a 2/0. The FD cut much cleaner also and it only had 35 TPI where the Olson had 46 TPI.
In conclusion, the FD cut much much better than the Olson. I may have to try some of their other blades. I have only used Olson's since returning to the scroll saw about 2 years ago. My go to blade in the Olson is the #2R reverse tooth,, I use this blade for about everything and love it.
Just my $.02
Barry