That looks like a killer boat. Price seems a little high. That engine will eventually kill the drive, but as long as you are EXTREMELY gentle on the throttle, it will last a while, and when it does let go, you can upgrade the drive with better parts to last longer. That is NOT a light boat. I bet everything said and done, full of gear and fuel, it is around 6000 lbs. ( My boat was 7280 lbs. on the trailer, nearly full of fuel, see below. )
I had a 26' Sonc, 1999, with a 500EFI. It was an awesome boat. I loved everything about it, and so do the new owners. The 28SS will give you just a bit more of everything, and they are rare to find with a single BBC setup. ( Most have twin 350 Mag SBC. )
We have long mentioned that a single BBC 28 Sonic with 700+/- HP would be a killer package. This is just that. The dash, throttles, guages, wheel, all look a bit updated.
I would try to get them down to around $25-26K depending on how many hours the hull has on it (if you can even find out). If it has a Rocket Aluminum trailer, deduct another $1000 bucks. (Rocket is the worst trailer on earth.)