Do you use a playpen? A baby safe room with gates? DD is not crawling, but rolls all over the room... I thought it was pretty baby proof in here until she tried to eat my laptop wire

I didn't want to do the playpen thing because I want her to explore... I also want her to be safe. I'm sure I could do both, and am considering purchasing a bigger gate/ play area for when I can't be watching every little move. What do you use?
Re: playspace ?
I use the playpen, exersaucer, or jumparoo (or a combo of several) if they are awake when I am still getting ready for work in the mornings and running from room to room.
I use the walkers if I am in the kitchen or laundry room (only tiled areas).
I let them roam/crawl/climb in their playroom or their bedroom if I am watching them.
We just use gates. I let her roam around the living room. She hates to be enclosed. The only problem is that I had to move everything that could be harmful out of her reach.
I purchased one of those large outdoor play yards, but she hates it, even though its really big.
We have this playzone from One Step Ahead and LO loves it so far (set it up yesterday and she had a great time last night and this morning):
https://www.onestepahead.com/catalog/product.jsp?productId=6193&parentCategoryId=85183&categoryId=85217
I was looking at that the other day. Would you think 2 babies would be comfortable playing in there? Without feeling like they were on top of each other? And do you think it is sturdy enough to set up in the grass outside?