When you put the upgraded bushings in replace the washers with some larger flat washers. The ones they give you are to small and tend to eat into the bushings and cause them to fail.
I never had a problem with my set up from RRO...
I think the washer bushing problem occurs from over-tightening and squishing the bushings...

There are 2 school of thoughts that I have heard...
1: You want the t-case to shift and move
2: Bolt that M|removethispart|@#%$ F&%$% down and allow no movement
I have heard good things about the brass bushing set.