Operating system name and version: Debian Lenny x86
Version of smsd: 3.1.15
Smsd installed from: sources
Name and model of a modem / phone: ZTE (model number is unable to find)
Interface: USB

As far as i have understood from here, there are 2 ways to send message via USB modem:
1. using AT+CMGS соmmand, when a sms text and number are pushed straight into modem.
2. using AT+CMSS, when text and number are placed into modem internal memory and, after that, message can be sent using pointer to its index in storage.

So questions are:
1. Which way of these two is faster for sending bulk sms sendings if i need to send set of inequal texts? Use +CMGS or use sequence of [+CMGW, +CMSS, +CMGD] ?
2. During +MGS usage i got 4-12 sec delay (here is 12 sec delay). What is delay caused by?