I have a Tiara, bought her in 2013, new in the box. I did not get the stitch regulator, I don’t like them. The only problem I experienced was learning how to get the needle seated correctly. I have moved house twice with her, no problems. I did purchase an extra bobbin case that I keep at the factory tension setting. I also purchased the leaves for both sides since I do make king and queen size quilts often.
I wind my own bobbins, I like using Aurifil 50 weight in the bobbin. I use a variety of threads in the top and the Aurifil works well. I check and adjust the tension on my own, just takes practice.
I just came off of an 8 month dry spell where I didn’t quilt. I just put in a new needle, oiled the bobbin case, checked the tension and she purred like a kitten!
This has been a wonderful investment in my quilting and I do not regret the purchase!