These are great (the Undersiders one too) I really enjoyed reading Worm, but it is indeed not for the faint of heart. Personally I found it quite a grim emotional rollercoaster, and dangerously addictive at times. It took me three weeks to read, and occasionally I would read "just a little more" in bed which led to the following thoughts:

“Who turned on the birds?”

“That time can't be right!”

“I am going to be so tired today!”

“Meh, worth it.”