Having experienced gut related issues recently that needed medical diagnosis I appreciate this direction of research wholeheartedly.
Been reading about pill based diagnosis for digestive organs for more than 10 year. Current alternative to this is incredibly invasive and painful and scary as hell!. Is any hospital using similar non invasice technology to run stomach/intestine checks?
There are some, e.g. the Medtronic Smartpill for motility testing:
Why would I want to put E.Coli into my digestive system?
Most strains aren't harmful. You already have buttloads (pun intended) in your digestive system. It even produces Vitamin K for you.
About 1% of your intestinal flora is composed of E. coli. Plus, in the system describes, the E. coli is enclosed in a capsule and won't colonize your intestine.