Well, I have had this machine for 3 years now and I am still amazed at it's durability, dependability, precision, and ease of use.
As a professional seamstress, my requirements are many. This little beauty has handled heavy zipper replacements in a tough fireman's jacket, bridal satin, organza (stabilizer underneath), heavy denim, quilting cottons, and knits. It's important to lift the fabric as it feeds into the machine to prevent dragging and motor wear.
At first, I would hear a clicking noise in the base and each time I traced it to the bobbin thread not being completely secure in the bobbin tension. The noise disappeared when fixed. Each time an error code occurred, I had either forgotten something (putting the foot down!) or I simply needed to turn the machine off, then on again. I clean it after each small project and several times during large projects. Flannels need this a lot.
Please read through the great manual several times so that you can enjoy all of the great features.
Wind the bobbins at a medium speed to keep the bobbin tension in line with the top thread's. Change needles when they skip stitches, snag, leave holes, or a different type is needed. I think companies are trying to sell too many needles and they're too darn expensive! Use an old toothbrush, q-tips, and the machine brush to clean. A 'little' dampness (I use what's on my tongue) helps pick up dust; and, get into all of the open areas while rotating the machine wheel to move the brush around carefully. This 'sweeping' should be easily done. Small vacuum attachments are the best for this. It eliminates trips to the repair shop!
Use cotton or poly thread in the bobbin when using invisible thread on top. Loosen the tension some because the plastic thread stretches slightly during stitching. Be sure to lift the fabric to keep gravity from working against you. Use a small (2-2.5 x 1-1.5) zip-zag stitch for knits if the stretch stitch is not to your liking.
Lots of great videos on YouTube. Save your money on books & DVD's unless that's your fancy. I have found that the old Reader's Digest Sewing Book is great. Many others are available. Read the reviews before choosing. Lots of pictures and simple explanations are the best. Use common sense and have a ball!