I love the Deutsch connectors. Really great stuff. I mainly use DTM for aircraft work (like Hugh alluded to). You can find complete tool kits on Amazon or eBay for them. I dedicated an old Astro aerospace crimper to the DTM barrel connectors.
Here is one tool kit called a "Tool Aid 18650" for $84 that can be found on eBay, Walmart (!), Amazon etc....
I recommend the machined barrel connector type over the open crimp-on type, just like most DSUBs. I have a real super-duper Deutsch branded crimper for the open type pins and sockets but practically never use it for aircraft work. Farm tractors and machinery, yes. But I stick to machined barrel contacts for airplanes.
You don't need a special tool for insertion or extraction of the Deutsch pins. A small flat blade screwdriver and small pair of needlenose pliers fit the bill.
I also like the larger standard DT connectors but typically only for larger circuits (18 gauge +).
After years of ordering Deutsch connectors and pins onesy twosy I finally ordered a complete kit from Terminal Supply Co. It comes in a nice metal case with individual compartments for connectors.
I had a bunch of great photos of DTM connectors I have used for aircraft applications on Photobucket before they went insane and I refused to be extorted by them and they deleted my pics. After the Photobucket boondoggle I rarely insert photos to internet forum threads anymore.
Examples of where I use them:
DTM connectors for the red cube fuel flow transducer.
DTM connectors for oil pressure sensors.
DTM connectors for under the panel manifold pressure sensors.
DTM connectors for stick PTT and trim connectors at the base of the stick.
DTM connectors for portable GPS bare data cable interface to panel avionics (GDL's, Comms etc...).
DTM connectors in the wing tips for LED strobe/position lights.
DTM connectors for wing root disconnects in case of wing removal.