I am also considering Dynamating my hatch, but i have read some threads saying it won't help much if you only do the trunk. What are people's thoughts on the effectiveness of just doing the hatch? I would like to not hear all the pebbles and stuff that hit my wheel wells. Also, how much weight does it add and how thick is it? (ie.how much height clearance would I lose) I regularly carry a pelican case for work that doesn't leave much height clearance so that is a minor concern. The mat's not like an inch thick is it?

It's nowhere near an inch thick. It's just heavy. The link below shows the technical details from Dynamat's website.

Dynamat Xtreme

I was quoted $150 for the Dynamat and $140 for labor. Is that a good price? Some threads make the process seem long and time consuming.

it took me a good 3hrs to do the trunk and part of the quarters. im sure a pro can do it in about 2hrs. considering $70/hr, that seems to be a decent rate.