Both are not particularly bright and sure not icepicky. The Flat 50 has a Nocaster character, so more 50's vintage flavour than the Boss. It's a quite chunky pickup though, not your typical twanger, more a big rocksound. Personally I think The Boss has more of the typical tele thing going, though with some compression by taking the 42 AWG plain wire to it's peak. The Flat 50 has 43 AWG plain enamel wire and is slighty hotter than the Boss. Both are muscular pickups and choice comes down to personal taste. You can rock out with either of them. Personally I like the grind of the Flat 50. Yet the Boss will never bother you with a too bright topend. And if you are a Springsteen-fan.....
By the way, you tame a tele with the toneknob. It is it's secret weapon. )
