what welding helmet to use

I have 2. One is an old school large viewing area fixed glass. The other is 600$ an auto darkening 4 senser multi setting. http://www.grainger.com/product/3MNX8?gclid=COe3str2kbwCFQdnOgodv0UA2g&cm_mmc=PPC:GooglePLA-_-Welding-_-Welding%2520Helmets%2520and%2520Welding%2520Protection-_-3MNX8&ci_src=17588969&ci_sku=3MNX8&ef_id=Up4AmAAABEU1TUkz:20140122135118:s

I never use it...