Here's a shot of our 2520 MVSC on the trailer behind my Yukon in the spring of 2001, just after sea-trialling and purchasing her from the Beaufort Boat House in Beaufort, SC. We're heading to Battle Creek, MI (1000 mi., +/- as I recall), thence to Little Current, Ontario, another 500 plus miles.
You can see the bunks (2 ea.) Neptune III rides on, which in my recollection were a full 2" x 8" on edge. If I knew then what I know now, I would have had the trailer configured so the bunks came all the way back to support the transom. The best setup would have the rearmost frame member of the trailer being a lot closer to the transom too, with less cantilever on the bunks. I don't think that trailer could be re-configured to do that; the whole trailer would have to be longer, because the winch stand can't be moved any further forward. Parker Boats would have to answer the question about keel rollers. I think they're a good idea, and Boston Whaler strongly recommends them for their boats, due to the strength of the keel. I think Parker's keels are a strong point too.