There are now two inlet barrier filters (IBFs) offered for the EC135 - one from Eurocopter and a second from FDC/aerofilter. AFS is also working on a third system.
Here in the States, the EC135P2+ has been outselling the EC135T2+ by about 3 to 1, though there has been some concern about P&WC's support in recent years due to its heavy focus on the PW600 turbofan (a situation that may improve now that the VLJ market has cooled). To its credit, TM has also been stepping-up its support, despite record production levels.
I/C