Lots of uninformed opinions and the usual suspects posting nothing but derogatory comments.
The Juggy is a f***ng powerhouse, it has one of the best spammable detonator in the game and it is health, shields and sync kill immunity allows it to stay and fight in situations where almost any other kit would have to run or take cover.
I played the Juggy a lot, but I have friend of mine who loves geth (GI, GE, etc) and he plays the Juggy a lot too. He can wipe the floor with good players using the Juggy (not me, it would not mean a lot, I mean I have a snowballs chance in hell to outscore him).
He usually plays the Juggy with the spitfire or the lancer (typhoon works too), with incendiary ammo + SP spamming. Here is the build he is using:
http://kalence.drupa...!33251364!.98AG
Of course the basic idea is to use SP offensively, prime with ammo then detonate as frequently as you can. For bosses fire all three shots at once since they strip shileds very fast, then prime with ammo. Ofc heavy melee only if you really really need it, otherwise backpedal and keep firing.
I love to use the claymore on the Juggy, it is a slightly different play style. I use SP to reload hide, which means that first I shot a target, then fire SP, which hits the same target and detonates the fire explosion (with incediary ammo). This style gives you 3 fire explosions for every 4 claymore shot (the 4th when you reload your SP). Here is my build, I love the big hex shield, less offense but much safer (portable RHA):
http://kalence.drupa...!33053364!G9.AG
Last but not least I love the crusader too, again it is different play style. Stack piercing mods, use drill rounds and geth scannner and exploit wall hax. In this case I keep SP for DR, somehow SP does not fits well with the crudader and you won't be detonating anything anyway. Ofc you can still use SP spam for bosses. Alternatively, keep the shotgun amp and use warp rounds:
http://kalence.drupa...!13N53343!G9.AG