When I bolted for slayer some time ago (before blocking -.-) I used around 40-50 bolts per Iron dragon, and 50-60 on Steels. Do the calculations. And as far as gear go, I simply used mystic, mage boots (wizard boots?), glory and lava staff. Don't forget you anti-fire shield :P And if you use antifire pots you won't take any dmg at all as long as you stay ouf of melee range. "Will it actually be worth it?" I ended up making some money using this, but i got some dragon drops, so I don't know how you would end up without that kind of luck.