Pros: musical influences for the ages
Cons: none if you don't appreciate good music culturing.
Once you tame this wild, noisy, amphetamine-fueled, out-of-control beast of an album, it will be your best friend for a lifetime. Few albums are as off-putting on initial hearing; fewer still will reward you more after hundreds of spins. Inexplicably, its chaos, noise, and howling confusion will become comforting. But it takes awhile...
For example, I doubt anyone ever thought they'd play side two (for those who remember vinyl) a second time after weathering the "I Heard Her Call My Name"/"Sister Ray" barrage...but if you can brave Lou Reed's paint-stripping lead guitar and John Cale's shrieking organ a second and then third time, slowly the initial repulsion will turn to compulsion. And the mysteries will unfold...20 or 30 years later, you'll still be trying to figure out "Lady Godiva's Operation" or "Sister Ray"...or at least basking in their glorious noise.
Songwise, it's not the best music the Velvets, Reed, or Cale ever made, but it's probably the most influential--would Sonic Youth, Yo La Tengo, Jesus & Mary Chain, Pavement, My Bloody Valentine, the lo-fi movement, etc., ever have happened without it?
"White Light/White Heat" is the sound of smart, cool, frustrated, and heavily amped (in all senses of the word) people coming apart and making as loud a noise as possible while they still could. And it's timeless because to this day it still irritates and scares people even after we've all been numbed by decades of hardcore, shock rock, and death metal.
Finally--the louder you play it, the clearer it gets. Volume is the key to this swamp creature of an album emerging from the murk...and the creature wants to be your friend despite its initially scary face.