Do you happen to work for Cisco or another large U.S. networking company perchance? Anyhow, I wouldn't put much association between such different divisions, anymore than I'd decide whether I like the LG N5X based on the quality of their refrigerators. In that case I'd either go by the initial hands-on impressions, or wait for a more detailed review in a couple of weeks.
On the other hand, if the issue is ethical to you rather than simply an issue of product quality then you are the only one who can decide.
The other key factor here is google. The nexus design team has said they partner with the OEM and the design process is not one sided, this was certainly evident last year with a very moto influenced nexus design.
That being said I don't think google would allow any blatant cutting of corners on the design.
I also feel like this year marks a shift in philosophy for google and the nexus line. The nexus now looks like a no compromise phone meant to go head to head with other flagships rather than being a cheap (price and build) option for stock android.
This is all my opinion/observation but I would say the only people who got nexus devices before were people who already knew they wanted it. The only reason most casual consumers walk over to the nexus 6 in a store is to figure out if it's a tablet or a phone. The nexus 6P will definitely turn some heads and bring some new people over to the nexus.