My opinions are based off of coming from the DX1 and Charge.
-Razr is EXTREMELY fast and snappy. Blows both the Charge and DX1 out of the water. I have to say that I do like the Charge's screen better, but it is far superior to the DX1. My biggest PROS
-Build quality. This is why I love Motorola devices. It is a great piece of equiptment, feels very solid unlike ALL Samsung phones I have used which are WAY too plasticky, scratch prone, cheap feeling and looking. I presume the G Nexus will be the same.
-Fast
-Stock email application (very important to me)
-No need to use a 3rd party Launcher IMO. The Charge lagged and Launcher EX was a must. The Razr is smooth and have not experienced any lag whatsoever.
-Battery - I actually dont mind the non-removable battery, it contributes to a more solid build. The performance of the battery is still up for debate, need to calibrate it for a week or so and mess around with settings. However, initial impressions is that battery life will be comparable if not better than the Charge. I can handle that. 13hrs-14hrs a day, somewhat heavy usage, 4 email accounts being pushed to phone, constant 4G, about an hr of phone calls, and a good amount of texting throughout the day.
If your buddy wants a reliable, solid phone that will last I would say Razr is the way to go. Moto radio's are top notch and can't beat the build quality. My DX1 looks new compared to the Charge. I have only had the charge for 5-6 months and it is all scratched up including the screen and I am pretty careful with my phones.
I am surprised he narrowed it down to Razr and D3??? Completely different style phones. Does he NEED a physical keyboard? If not, its a no brainer in my opinion.