To get a list of accelerators through the Assembly class you can use the statement
and on my current workstation with PowerShell 4.0 there are 80 accelerators.
GetType()has three implementations, and the one with three parameters is used to get the most stable and predictable invocation.
The class TypeAccelerators is private, but accessed through a PSObject object.
Some accelerators are named in lower-case and other in mixed casing (CamelCase). Generally I prefer to use the casing that the accelerator has in the definition.
I have not seen any indications on a performance hit when using accelerators. And as the code is so much more readable with accelerators I go with them where it is possible.
When it is not possible I use the full class name, e.g. "System.Data.SqlClient.SqlConnection".
It is possible to create custom accelerators like an accelerator for accelerators:
The accelerator is then available like any other accelerator:
This accelerator is part of some PowerShell extensions.
Personally I prefer to name custom accelerator in lower-case.