I use newspapers but can see an advantage to having something you can roll out like that. How heavy is it? I've bought newspaper print on a roll before but not to use in my garden. Builder's paper is probably heavier.

It's much heavier than newspaper. It's similar in weight to butcher paper.

Tempting. I'm going to look for it next time I go to Lowe's. Newspapers are tricky to work with if it's a windy day. You have to overlap them so it's a bit time consuming if it's a large area.
If you plan to leave the paper there and mulch over it, you do want something that will eventually break down and would let moisture through until it does.

I think it should breakdown. I don't see anything about it that would prevent that from happening. As far as I can tell, it's just really thick unbleached paper. It probably won't break down as fast as newspaper, though.

I use cardboard - we get lots of box deliveries, so I just flatten them and cover over - breaks down well, really kills everthing.

I use cardboard too. It is free. If one is looking into covering a large areas, I have found that buisness that ship in solar panels have GREAT cardboard boxes for this. Heavy , large.