Is this package enough bass for a daily driver?

Yes, for filling in low end under music. At 245 watts RMS it adds warmth and punch but will not deliver heavy competition-style output.

Will the shallow sub fit behind a truck seat?

That is the point of the shallow-mount design. Measure your mounting depth and the sealed box dimensions against the space you have before buying.

Do I need extra parts to install it?

The amp and wiring kit are included. You still need a power wire run to the battery, a ground point, and a signal source such as a head unit with subwoofer outputs.

Can I upgrade the sub or amp later?

The enclosure and wiring are reusable, but the amp is matched to this sub's power. Swapping in a higher-power sub would mean a new amplifier.

How does it compare with a ported box?

A sealed box like this is tighter and more accurate but less loud at the lowest notes. Ported setups go deeper and louder but need more space.

Does it work with a factory stereo?

Only if you can get a line-level or speaker-level signal to the amp. Many factory head units lack subwoofer outputs, so a line output converter may be needed.