Wouldn't that super lag anyway unless you make like a 64x64?
what do you mean
it'd lag about as much as if you were to build it by hand after it generates
the only time it'd probably lag is if it made a huge landscape that had tons of bricks in it (which may take awhile to actually lag unless your computer can't handle it) or MAYBE whilst building (that kinda depends on how it's building, you can make it lag a lot less pretty easily).