When I bought my pfaff almost twenty years ago I asked the dealer if I should bring it in once a year for service.
"Ah madam": he replied, "when we give it a service we blow it to clean and put some oil in it....you can save money by doing that yourself."
So I did, and still do, my machine has never been back to the dealer.
And the dealer was one of the two bestknown for good service in the area.
But with the machines of today?? Don't know if I should do the same, they're not all the workhorses the old ones used to be , I hear people say

I've had my Pfaff since 2002 and have never had it serviced... I clean out the lint and do a drop of oil a few times a week. Once my new Juki's are up and running I'm going to take her in just for my own piece of mind... She deserves a "spa" treatment after all the work I've put her through!

I take my Bernina 440 in annually for a 'tune-up' because it's worth it. She was expensive and I can't afford a new one right now. As my one and only (except for her cousin - my Bernina serger) I depend on her a lot. I'd rather spend money getting her tuned up each year and have a little less for fabric than have a bunch of fabric and a broken machine.

I purchased a Service Maintenance Agreement with my Bernina 440, and when that expired I purchased another one. It covers anything that goes wrong, service and parts, and is well worth the money. Because it doesn't cost me anything additional, I take the machine in whenever we're going out of town for a week or more, usually about twice a year. The machine gets checked out, completely cleaned (I am diligent about regular cleaning but I can't get to everything), and any electronic updates are loaded into it. The dealer where I purchased it has an excellent reputation, and they give me a good estimate of how long the repair shop will have the machine.

I do have several backup machines, and they don't get the same treatment. However, they're from another era and don't expect to be pampered.

I take my Bernina in every year to be serviced. Other machines that I've had over the years never were serviced and always sewed fine. I clean my featherweight myself.

When I first bought my Bernina I took it in regularly, because of my warranty, but now, I won't take it in unless Im having a problem with it, which so far I have'nt. If you have a warranty and don't get them serviced, it voids the warranty.

My Viking Sapphire starts to be a little more noisy when it needs service.
The problem is I moved to the mountains and there is no place to take it unless I drive 3 hours to Phx. Then would have to go pick it up.

I do every year, but my dealer sells service protection plans, which cut down the cost of servicing the machine and you can bring it in whenever you want as much as you want and if something breaks parts are covered like motherboards which we all know can be expensive. I damaged my bobbin case walked right in and got handed a brand new one, It was that simple.its like 3-600 dollars for 4 years depending on your machine model. I am about to renew mine because my service plan for my espire transfered over to my new machine but I only have a year left, and I know embroidery machines can be very sensitive especially the tension diskc so I really want to renew it

I used to do yearly. Now I do by how much I have used it or if there is a problem.

I have a 30 yr. old Kenmore when they were all metal. Hubby oils it regularly and I clean it and use a small vacuum attachment on it regularly. Only had it to a shop once and that was recently when it was having trouble feeding fabric smoothly (couldn't chain piece). I'm not about to give up on this workhorse!