Weak hand ejection and reload is faster and more consistent, in my experience. With decent speedloaders (not HKS or another twist-top design), I have also found that technique provides less opportunity for the empty speedloader to get hung up in or around the cylinder, and I have greater visual clearance into the chargeholes when briefly confirming loader alignment.
The process starts the same whether using a sprung loader (Comp III/JetLoader) or a gravity fed loader (Comp I/Comp II):
Right thumb release, left fingers push cylinder out of frame, muzzle up, left palm eject, gun and left hand go towards belt, muzzle down, left hand grabs loader, left middle finger indexes between two rounds, brief visual confirmation that the indexed finger is coming down on the bridge between two charge holes.
Sprung loader:
Left hand holds loader with rounds started into charge holes, right thumb presses on base of loader while left hand releases loader body, empty loader falls away, left palm rolls cylinder back into frame, gun meets eyeline back on target while reestablishing grip.
Gravity loader:
Left hand presses loader body into cylinder while right hand pulls the gun towards the loader, left hand releases loader body, empty loader falls away, left palm rolls cylinder back into frame, gun meets eyeline back on target while reestablishing grip.
The sprung loader technique cut my reload time down from about 4 seconds to under 3, shot-to-shot, in match conditions. It’s not going to work for everybody, or for people with body-types not conducive to carrying speedloaders in certain locations on their body. But, it’s enabled me to stay within 10-15% of overall match times compared to the local SSP and CDP MA class shooters (granted, that doesn’t mean a lot since the 5x5 became the IDPA classifier).