I interviewed with ACT in Aug 2016. The waiting period between interviews was long and spanned for 40-50 days between initial HR contact to the final decision. The first round of interviews was a 30 min telephonic conversation with 2 R&D engineers. The questions were mostly resume based and were trying to check my compatibility with the job requirement. Later, I was called for an onsite interview at Lancaster, PA. The day was laid out like: Technical presentation (30 min, on any topic of my choice), 5 in-person interviews (30 mins each), followed by a facility tour. The interviews were fairly technical with a few behavioral questions. The overall experience was average.