As everyone else here has said, this Chessex megamat is excellent. It's much better than tiles, which are (a) expensive, (b) unique (your players will start joking about having been in this forest before), and (c) unstable at the table. This mat has enough friction on both sides that it basically sticks to a smooth, flat surface, so you'll never jostle it out of position. (No guarantees for jostling the minis on top of the mat, of course.) And it's just the right size to fit on a dining table for 6+ people.
A few tips on how to get the most out of this mat:
(1) Clean it thoroughly between sessions. I usually give it a once over at the end of each gaming session, but then I take it home and clean it again (wet paper towels are sufficient). You'd be surprised how much ink can stay in the mat's fibers even though it's not visible.
(2) If you must store it rolled up, roll it so that the side you use (squares or hexes) is on the outside. That way, when you unroll it at the table, the curl goes downward and into the table, rather than upward away from the table. This makes it easier to flatten.
(4) If, as in my case, your mat does not live in the same place where your gaming sessions occur, I strongly recommend picking up a carrying tube. I just picked up an Alvin Ice Tube 37" (for example, Alvin Ice Tube 37 Inch Blue) for this purpose, and it's great. Besides allowing me to throw away the flimsy and battered thin plastic sleeve in which the mat was originally mailed to me, the tube is also fairly wide in diameter (2.75 inches interior), which means the mat doesn't have to stay so tightly coiled up in storage.