Frequent readers probably remember the "grip of death" issue that affected Apple's iPhone 4. Basically, since the smartphone's non-insulated antenna was placed around its sides, holding the handset the "wrong" way resulted in significant drop in signal strength. That's why Apple eventually gave away tons of iPhone 4 cases and $15 refund checks to affected users.
Interestingly, the antenna on the Nokia Lumia 925 sports a very similar design as it is wrapped around the sides of the smartphone. Will that cause any signal strength issues? Well, chances are slim, as this brief demonstration shows. No matter how the smartphone is being held, its signal reception remains virtually unaffected, without dropping a single bar.
So yeah, if you have your mind set on the Nokia Lumia 925, then you can now rest assured that the smartphone won't be dropping calls regardless of how you're holding it. See the proof for yourself by jumping to 2:30 into the video below.