Personally I don't use it. I purchased (for about $15) a mini kit that attaches to my vacuum cleaner. It has very small pieces that allow me to suck out all the lint in my serger and sewing machine. I think it was designed for computers, but it works great for sewing machines.

I've read that using compressed air can blow lint into areas that can't be reached and do more damage.

My sewing machine dealer told me not to use it. It can force lint into places it shouldn't be. I also use a mini vac attachment to clean my sewing machine.

Also, my dealer told me that dust and lint are the sewing machine's worst enemy. That if I kept mine clean, it would serve me well for a long time.

So you are right to be concerned.

Compressed air is not good for computers either unless you are blowing it out of the pc (inside to out). For my Viking, I find the vac works best too but before I start that, I fold a pipe cleaner, (one of the large chenilles ones) and work that in the open spaces. It is amazing the amount of lint that will stick to it. The one thing I dislike about my modern sewing machine is the inability to gain access to the inside! Like some computer cases, I can't find the open sesame :-)

My sewing machine tech showed me a machine with a terrible accumulation of lint that had been blown back and was literally PACKED into the machine. It really made a believer out of me! I too use a computer vac for my machine (never canned air) and also have it cleaned and serviced annually. The air in those cans contains moisture, as does your breath if you blow into the machine. Both can cause rust. My Berninas are too big an investment to take chances. I've checked with dealers of other brands sold locally, and they also don't recommend canned air.