Here are the specs of the 10" JL W3:
Nominal Diameter: 10 inches (250 mm)
Continuous Power Handling: 250 Watts
Voice Coil: 2.25" diameter, 4-layer, Kapton former
Available Configurations: Dual 2 ohm, Dual 4 ohm or Dual 6 ohm
I personally wouldn't do a triple sub setup only because there's a lot of risk factors. you can just imagine the possibilities. BUT if i was going to, i'd invest in a strong JL Audio or a good class D amp. Nonetheless...i'd stick to two