I can concur, the TH-900 are perfect headphones for a bedside rig. They are comfortable, have some noise isolation, they do leak but are decent at that as well. The sound is perfect for movies and gaming IMO. Nice soundstage for gaming, excellent bass for movies, and they sound great with almost any genre of music. If you are the type of person that likes to just relax and enjoy what you are listening to in bed, then the TH-900 will be great for your needs.
When you guys say bedside rig, hope you don't mean literally. I have fear of breaking my TH-900s as a bedside rig. I think long time TH-900 readers will probably know that I've had my TH-900 cup swivels broken twice in less than a year's worth of owning these cans. I've been using my Signature DJ instead as a bedside rig.
As per PM. I commend Tokendog for attempting to answer your questions however I think they are difficult to answer objectively as it's all relative. I don't know if anyone can authoritatively answer you if the TH-900 has enough bass for electronic (for you).
Also, if I may be so bold to speak on behalf of the TH-900 fans here, the beauty of these headphones really has to do with its ability of presenting sound quality such as rendering of bass, clear airy smooth highs, open soundstage despite being a closed-back design, and 3D imaging; rather than just simplified to "bass quantity". I'm horrible with analogies but at the moment I can't resist throwing one out there - it's a difference of enjoying a nice glass of full bodied red wine, as opposed to just simply "will it give my head a buzz".