Our VAR was Trimech for many years, then we tried a few others that were worse, and finally we came back to Trimech.
We've always lagged a year behind the current SW release to try to avoid getting hit by the latest and greatest bugs.
I think we just hit more edge cases than other companies. We have half a TB of stuff in our vault (about 250k files), going back to 2012 for the first import. Lots of legacy files, fairly complex assemblies, heavy use of some tricky stuff like the sheetmetal design tools (where we tend to find the most bugs). And then there's Solidworks Electrical, which I don't think anybody is set up to support well, as it's still a fairly recent acquisition from Trace Software.
I've never once run into something that they didn't have a workaround for, and then eventually fix. Sometimes it takes a service pack or two.
They out out 4 or 5 service packs every year along with the major yearly releases, those service packs are basically entirely bug fixes.
You may want to look into switching VARs if your not happy with your support.