Traffic Shaping

Lets say I want to break up a T1 into 2 speed groups; fast and slow.
Say fast is 1000kb and slow is 450kb.

Should I have 2 pipes; one 1000kb to handle both in and out, and one 450kb for both in and out on the slow group.

Or should I have 4 pipes; one 1000kb incoming, one 1000kb out, one 450kb incoming and one 450kb out?


Thanks

Answered my own question.

I need 4 pipes for this scenario. 2 for incoming and 2 for outgoing.
Seems to work well.