I've had mine less than a month, but I haven't seen any grease dripping from anywhere but the drain pipe. I've wiped off a few streaks from the front, so maybe with a really long smoke, it might drip down the front and onto the ground/deck/etc. There was a good bit of silicone caulk down in the bottom of mine along the edges. This might be something that they didn't do in the early days?
Out of curiosity, if you only want something for grilling, why aren't you looking at their charbroilers? The direct side on the PG500 is small, compared to the rest of the surface area I mean. Don't get me wrong, it's plenty big for a few steaks or 6-8 burgers, but I feel like it would be a waste for you not to use the indirect space at all. Who am I kidding, if you buy one, I'd be willing to bet you use it for more than just what you think. I've made brownies on mine, cookies, pigs in the blanket, it cooks anything!