I don't think the 282 was ever outfitted with 300s. However, the performance will likely be similar to a 285 if properly set up. You can see numbers for the 285 on the GW website. I'd guess 2-3 mph less on the top end and 0.1 - 0.2 less mpg at cruise.
On another note, I'm a bit surprised GW offers the 285 with 350s. A 60 mph bow rider is nucking-futs! I feel like GW is getting a little too caught up in the marketing game that car manufacturers play. What looks good on paper sells to the uninformed, while being a safety risk to those on board. Maybe GW will start offering seat belts and air bags? The average safety conscious consumer is all-about those = more profit!