You are not planning on running a lot of power, and can get away with a bridged 2-channel AB amp, as long as your sub's final wired load is 4 ohms, if th eload is 2 or 1 ohm, than you really have no choice but to run a D amp, which gives maximum power output at your sub's final impedance.

Also, if you're overpowering, the sub enclosure plays a big role. The bigger the box, the more efficient the sub becomes, therefore, hiking the chances of sub's overexcursion, but if the box is made to the sub's recommended enclosure specs, then you're good.