[Sox]

Well this seems to have fallen a bit flat.
Only 2 sets have been made so far.

One known to have been fitted with excellent initial results, only to have had premature rubber failure after a week or so.

The other set has been supplied sometime back, but it's unknown whether they've been fitted.

The set which had premature rubber failure is a bit of a bother. The rubbers used were the Kelpro - 23036, which I found to be the correct size needed.
The guy (Stonypony) who fitted them felt the actual problem is the spring saddle alignment on the shock isn't correct, allowing the spring to sit somewhat crooked, thereby locating the shank non central to the shock mount.
From memory they were KYB aftermarket shocks.
From what I understand he has now fitted poly bushes and also a locating washer.

Personally I'm not convinced of this theory, as I feel once the spring is under compression, the lateral forces on the shock shank would continually change.
I also would not recommend a washer be fitted between the rubbers, as premature wear could result as the washer grinds into the shock shank.

My own thoughts as to why the Kelpro rubbers failed are -
1 - The bushes aren't designed for the lateral forces involved with an integral shock spring setup (essentially a strut).
2 - The KYB shocks possibly have a longer shank, thus not allowing enough compression of the rubbers.

The only thing I can really do now is to not recommend the use of the rubber bushes, at least for now, until I can determine the actual cause. Or at the very least, use them at your own risk, potentially having to swap them for poly at a later date.

I understand if this puts some people off, as I certainly don't want to provide something which whilst removes several flaws, introduces another new one.

jeffb - How are yours going?
tkfd - Are yours on yet, have you sent the old ones back to me?
Stonypony - Do you have any feedback on how the new poly bushes went.

BTW, Stonypony also found which Nolathane part number is the correct size - 43036.

For the record, my own prototypes are still performing flawlessly after many thousands of km, using old rubber bushes from a live axle setup.
I haven't changed to poly yet as planned, but may get some time this weekend.