The Esteem is powered by a 1 GHz Qualcomm Snapdragon processor, which is able to run Android 2.3 fairly smoothly. The higher end Galaxy S from last year is pretty comparable to this smartphone. It's actually quite a refreshing addition to MetroPCS' line-up, and snuggles up alongside the recently released Samsung Indulge. There is a bit of lag occasionally when switching from processor heavy applications but really, it's not that noticeable, especially for an entry-level smartphone.
The call quality was not the best, the volume was a bit on the low side, even at max volume. The voices themselves were clear, it was just the volume that seemed low. Outgoing calls were fine, with no major distortion. The data speeds vary depending on location, but the Esteem is a 4G smartphone. MetroPCS doesn't have as robust a network as Verizon when it comes to 4G LTE, so certain areas will not have the faster data speeds available.
While the battery size is 1500 mAh, similar to the Galaxy S, it seems the life of the smartphone is much shorter. It barely lasted a day with regular usage, including calls, browsing and messaging.