The other thing to consider is security. If you have access to your corporate email on your phone, or if you access sensitive personal info on your phone like bank or credit card info, security is becoming more of an issue. It seems weekly now we are getting reports of major malware being discovered for Android. I believe only Google has guaranteed monthly security patch releases. The only other Android manufacturer I would have any faith in at this point, from a security standpoint, is Samsung. However, I still doubt in their ability to get security updates out to multiple phones and through multiple carrier certifications as quickly as Google will be able to do for Nexus phones (which is why I will only buy Nexus from now on).
Honestly, if you are buying any other phone other than a Nexus, I would strongly urge you to look at some anti-virus app in the Play store.
AVG and Avast seem to have the best ratings (4.5 stars) and both have a free version. Paid version for Avast is $15 annually, no price shown for paid version of AVG. Having looked at both of these just now, they seem to have some neat options, making me consider trying them out just for the extra piece of mind.