Using the adapters inside the airplane works fine too. There is a SMALL added resistance because of the extra connections. You'd have to do careful testing with a wattmeter and motor test stand to see the power difference.
I have a deans to 4mm bullet adapter in my big EDF. The EDF came with Deans (for a motor expecting 100 amps continuous...) Changing that connector would have voided the warranty on a 1400 EDF unit. (yes, I called BVM and asked)
I went with a 100 watt high temp iron so I can solder large gauge wire fast. The 40 watt irons take a while (never hot enough if using lead-free) when working with 8 gauge.