esd safe isn't all that important for generic soldering but if you plan on reworking anything with ic's eeproms etc. ever it's not a bad idea infact I wouln't buy one thayt wasn't just because it doesn't cost anymore that non esd and why chance it or why have to buy anothein the future... I have...
Ok here is my generic analogy wavelengths. Radio waves are similar to sound waves in the sense that high frequencies tend to become excited and erratic when obstructed (treble becomes washed out distorted and tinny reflecting off of glass)Microwaves create heat by the waves bouncing off...