Interviews on Client Site

I have interviews set up for a Big 4 form but it's on the client site. HR already told me that they have some long term roles but this screams staff aug, high stress situation. I'm currently in a staff aug type of role at a 'boutique firm' so I'm hesitant in pursuing this opportunity if it's going to be the same thing. Does anyone have any insight into client site interviews and if this spells disaster.

Thanks.