We took delivery of our 2016 Montana 3100 RL in April. We almost ordered a 3160 but did not want to give up the big door side window and could not find one with the Legacy package. Anyway you have a really nice unit with the outside entertainment system and a awning on that slide. As for quality, fit and finish we have been very happy with ours. Only a few minor problems like a loose ceiling fan blade, loose rear ladder and toilet not holding water. All repaired by me so it has not been back to the dealer and we have spent about 25 nights in it so far. Our unit was ordered and built 4/14/2015. I think you made a good choice and hope you are as happy with yours as we are with ours.
On edit- One reason we went with another Keystone product was our 2007 Laredo bought new was flawless the entire 8 years we owned it with over 400 nights spent in it.