For what it's worth;
My Hellwig Big Wig is getting a new set of bushings; both the D style and the rod ends, for free from Hellwig. I called 'em, told them that the D's were wearing and they are sending me a full set for free. (lifetime warranty)
I've also ordered the front rod bushings from Rock Auto. I'm on my 4th set; the factory originals and 3 other brands. The bushings don't wear out, they dry and crack apart! I would bet they would fall apart in a year's time just sitting on my workbench!
So, I'd have to say the bushings are something we need to keep an eye on and plan to change regularly.
Do a search on Rock Auto and you'll find several manufacturer bushings for your needs.