I like putting it this way. Tell them it's a phone for Android enthusiasts. Kinda like why some people would buy an BMW M3 vs a regular 3-series. They make look the same on the outside, but it's what's going on inside that counts
Funny timing, I just took my M3 for a very important drive. To the liq for beer!! The one big difference between the phones is the locked bootloader. It's like the 328i's hood wont open so you cant touch. The M3's hood on the other hand opens with ease!