so im looking at getting a 4 string thunderbird and obviously there are a ton of different models/years/sounds and i wanted some opinions on each one. i play detuned sludge/stoner metal kinda stuff and id like to know which would be my best bet for that "huge" sound. is it worth the money to try and snag a 70s one? would i really notice the difference between and epi and a gibson? do the 90s models sound different than the current models? any info would be helpful, i need to start hunting soon!