Hi Bob,
First off, thanks for supporting the board and good luck with your search.
A couple of comments.
If you're new to boating, you might want to work your way up to running at 80 MPH. That's real quick on the water. And it's trickier to drive at 80 in a small boat, versus a larger boat. To do it in a large boat, you need big outboard power.
You asked a few questions, which I didn't really see get answered, or perhaps I missed the answers, anyhoo.
Some Checkmates have what they call a pad. The simple explanation of what it is, is this. It's a flat pad that is located on the very bottom of the hull. If you look at the back of a boat and the very bottom of the V is actually flat and it extends out each way from the center, that is a pad. Pad boats tend to run faster. And the wider the pad is, usually the faster the boat will run and wider is sometimes a bit easier to drive. More or less what a pad does, is allow the boat to get up and run on just the pad at speed. So the hull is less restricted and runs faster. IF the pad gets too wide though, it can effect the ride quality, so like most things in life, it's a bit of a balancing act. Many of us would like to see Checkmate widen the pads on their boats a bit, so they would run even faster. And some members have modified their boats so they have wider pads.
I think that's why a few members latched on to the boat that you said had a widened pad.
On the black boat that you looked at that needed to be buffed out. Buffing and waxing fibreglass will no doubt make it look better. But if the gel on the deck has seen better days, what will tend to happen is that wax will make it look all shiny and new, and then as soon as the wax burns off, you'll be back to the dull deck you had before. The boat will more or less look as good for as long as your wax holds up. That's why a few members mentioned the black boat might need to have the deck shot with clear. Meaning, it be sprayed with a clear coat to make it look better, and better longer.
I have one suggestion for you.
Before you hand over your money on any boat. Get a good inspector to look it over. Many boats that are older can look great but need work that isn't so apparant unless you know what you're looking for. One good reason is this. Wood is used in the building of fibreglass boats, it's used for the floor, stringers and transom to mention just a few places, and wood can begin to rot. A proper marine inspector should be able to find any trouble spots before you purchase.
Same deal on the motor. Motors can run great and have zero compression. Some of the smoothest running motors can run smooth as silk, but make very little power. I've seen that here time after time. We've had a number of threads where a member can't figure out why his or her boat is slower than the average, and when a compression test is done, the true story is told.
So at minimum, you want a compression test on the motor.
At the end of the day, whatever you buy will eventually break. That's just part of the hobby. You break 'em-fix 'em and then break 'em again.
But it is nice, to at least get a few good rides before you dole out some more cash.
Good luck with your search!
-Chris