ShopTalk Forums | Aircooled VW Tech & Restoration Help

I know that these are sometimes used on the exhaust studs of our beloved heads, But are they usually needed in the case? I believe that type 1 cases are usuallu in need of them (due to waeker cases) but do the type 4s usually need them? Are they good insurance?

TIVs only need them when an idiot has destroyed the threads.
Our case is Die Cast aluminum and is strong enough not to need inserts.