SDG #086 What’s the best flux for soldering? A comparison with PCBs from JLCPCB

$2 for PCB Prototype(Any Color): 1. Yellow Solder Paste: 2. Mechanic MCN-UV80: 3. Pro’sKit 8S005: 4. Weller F-SW21: 5. AG Termopasty TK83: 6. AG Termopasty LP-1: 7. CIF F42202 Gel Flux: 8. MG Chemicals No Clean Gel: 9. Best BST-223-UV80: 10. Relife RL-421-OR: 1