Next, the center navigation button has been replaced with an iPod-like click wheel that rotates both forward and reverse along with doubling as a 5-way navigation. We noticed very few accidental key presses while the phone was up to our face. This could be the single greatest improvement on the VX8550 which makes navigation and phone use a breeze. The slide mechanism seems as strong as the previous model with solid open and close motions. LG seems to have one of the best slide mechanisms on a mobile phone (Samsung, you're a close second).
Call quality was on par for newer LG phones with great sound for both incoming and outgoing calls. None of the people we talked with could tell that we were on a mobile phone even with moderate signal strength. We even managed to stay connected in low signal areas where the VX8500 dropped the call. The VX8550 supports Bluetooth for voice calls and also for stereo music listening. We paired both the Motorola H9 and a Jabra JX10 with this phone. Both headsets performed as expected in close range, however at distances greater than 15 ft. there was both audio dropouts and fading.
All in all, there are several enhancements that gives the VX8550 clear advantage over its predecessor including the center navigation, updates to the keypad, and overall styling of the phone. But with a cramped keypad and smaller form factor - it might be passed up by those power users looking for a roomier layout.