On that particular landing page we did not; however, we've since done some testing on our site, and found you're really best to stay under 2 minutes. 60-90 sec

On that particular landing page we did not; however, we've since done some testing on our site, and found you're really best to stay under 2 minutes. 60-90 seconds is optimal. Attention span metrics really help with measuring your particular audience though - as it heavily depends on the message you're sending.