Depends really on the available system resources and will be different on various systems.. I'm using TS version now.
Idle memory usage is not only the factor that makes a product light. Memory usage on scanning, processor usage etc, file transfer, network speeds, file open times, boot times can be included into the mix.
you need to completely disable it, killing all its process to see the different.
the same story with MSE it shows 70MB but when killing it you gain a lot more.
of course for someone that has more than 2gig its not a problem but if you have only 1gig you have a problem