When your computer reports a speed of 19200 bps, it is referring to the speed across the cable that connects your computer with your phone. Aside from the obvious difference that it's wireless, the biggest difference between your Sprint PCS Phone and an ordinary modem is that there's no modem in your Sprint PCS Phone, PC, or laptop - the modem actually resides within the Sprint PCS Nationwide Network. However, to your computer, your phone looks the same as an ordinary 14400 bps external serial modem. To you, the important difference is that your connection is wireless.
Several factors can affect battery life.
Low signal strength will reduce your battery life because your phone must use more power to transmit and receive signals. Also, transmitting data uses more power than receiving data. So your battery life will drain faster when you're transmitting data than when you're receiving it. Using your phone to end a data or fax call won't usually cause problems. However, because some software may react poorly, it is recommended that you end all wireless web calls via your computer software.