The brother 1500 so is mechanical. Doesn’t have speed regulator. But it has fabric feeding feature that’s way more important to me. Why is speed regulator important?

Okay. I was looking for the specific ones you cited. That's okay. Nevermind

I want a speed regulator because I have a quilt pattern I want to make and it needs to be machine appliqued to the square.

I looked at the Juki TL2010 and the Janome HD9 before I purchased the Juki. Difference for me was the Janome did not drop the feed dogs you have to buy a special plate that covers them. Yes the bobbin holds more thread but the price difference and lack of dropping feed dogs made Juki my choice.

That would have done it for me. I mostly use my Juki for FMQ

Maybe we are using different words to describe what you are looking for? I do lots of machine appliqué and not sure I would want a speed regulator on it. If your piece is curved like for instance a flower, you would want to be able to stop and start in the spots where your needle would be down on the outside curves. Sorry if I am misunderstanding what you are looking for.

I am wanting to make the pattern Starburst by Me and My Sister Designs. Donna Jordan has a tutorial on this pattern on her Youtube at Jordan Fabrics. It has to be machine appliqued and I have never done that before and I would imagine I would want to go around those blocks slowly. I am not making a table runner like she made. I am doing a full sized quilt.

Just looked at that pattern, very nice! Well my machine is a Husqvarna Sapphire and it has a button that I can control how fast or how slow it goes. Is that what you are looking for? A stitch regulator is usually used when doing machine quilting.