I subscribe to several large mail lists, receiving hundreds of messages each day. When I am at home I use Outlook 2000. It's not the greatest newsreader, but it offers a couple of timesavers:
I can group messages by conversation topic, allowing me to easily delete entire threads that do not interest me.
As I read messages, I can selectively delete (or not) the current message, and the reader will automatically display the next message without taking me back to the main message list where I must scroll to where I left off and identify the next message and select it.
Can either of these functionalities be obtained in the SquirrelMail reader?