I do both - but only within the past two years have I started hand washing. Once or maybe twice a year it should be an 8 hour job.
Tim, this is a whole other area to get into and there is some good info in the detailing threads. Until about two years ago I hand washed only occasionally. Now it's the norm, unless there is a huge amount of build up. Then I'll do the drive through just to do most of the dirty work. But I always try to go over the entire car again with a quick detailer.
Clay bar and wax cleaner, sealant and sooooo many types of waxes really make a HUGE difference. If you have the patience to take apart your interior and have the attention to detail that so many of your posts illustrate - I'm actually SURPRISED you don't take pride in your Tchuck special hand wash detailing extravaganzas!