The e61 require more cleaning than the lever because they vent back through the group and take all the crud with them
My e61 routine is :
Make my two coffees. Flush the group into my pot, back flush with water, this is religious after every coffee session.
The screen comes down once a week, my water is practically inert so bacteria can’t really grow in it, the tub gets a monthly clean.
The levers :
Finish making coffees, flush the group into my pot. After every shot.
Tub once a month
Shower screen on the Evo after 5-6 weeks
I really don’t like using chemicals on the machine.