...Makes the repair Easier, Yes, but not the best conductor. The resistance is higher with the crimp connectors as the wires merely make a contact. Increased Resistance will heat up the Connector, and a constant Heating and cooling will, over-time, loosen. Soldering brings the conductivity to the Molecular Level, with a lesser resistance, and these will Not pull apart.
I have used the Correct Crimp Pliers, and I have had a 10 Gage wire pull out, The Main Supply from the Amp Gauge, It Cost Me $$$ Greatly. Never Again!
One would ask themselves...do the job right or do the job Easy, and then do it AGAIN! It is My Opinion that those Connectors are meant as a 'Easy', Temporary Fix.