A G11
single piece worm block, $295 USD from Losmandy. Available very soon. Thing is you use your existing worm in the housing.

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This would be fine if all G11's had the high accuracy worm, but not all do.
At $295 it's a lot cheaper than
Ovision, $499 USD.
The reported improvement is 40% better PE. Mine is around 7 Arc seconds P to P thus expected improvement should see this lower to around 4.2 Arc seconds.
I was kinda was hoping for at least around 3 Arc seconds P to P or less...maybe I'm dreaming too much.