Though i would post this in case it helps other.
When i replaced the entire suspension of my E46 3 years ago, i used Meyle hd wishbones and carrier bushings. I was very impressed with the price and service from allgermanparts.co.uk based in Leeds. (just for clarity i have no connection with them)
I had the e46 up yesterday and the arms look as new. very impressed, (they have a 4 year warranty)
This morning i was looking for thrust arms for my Beast, these are the options i had..
1. OE Lemfoder from eurocarparts at £122 each side £244 the pair
Lemforder BMW | Euro Car Parts UK
2. Replace the bushes with powerflex or X5 or Meyle HD probable about £60 but would need to rent or buy the tool to press out the bushings at £40 - £160 and would then be left with a balljoint that had done 82k miles and the hassle of fitting on the car or risk damaging the balljoint removing.
3. Buy new lemforder arms at the above price and retrofit powerflex , X5 or Meyle bushes (this was my preferred long term solution but is expensive) about £300 ish.
4. Import meyle bushed lemforder arms from EAC as mentioned in a post on here about $325 plus shipping taxes so about £300.
i remembered allgermanparts and gave them a ring to see if they happen to do an e39 M5 meyle hd arms
MEYLE-HD
Well, the very helpful chap i spoke to enquired with Meyle and they have an HD arm for the e39 m5 that they are about to introduce into the UK.
allgermanparts will have mine in in two to three weeks at about £80 each !! including a 4 year warranty.
hope this helps i think the quality is spot on and at that price...