PLB or LVS for load balancing apache

I wonder which one I should use for load balancing apche:
- Pure Load Balancer (PLB)
- or Linux Virtual Server (LVS)
Currently there are 2 Webservers for the load to share on.

Does anyone have expirience with one these?
I also need to keep track of the php-sessions. Do you think Sharedance
is good for that?

Thx

P.S.: I'm aware of pound, but what i read it creates much overhead, so i
don't think it would be the right thing to go with...