S2 was built by Leon Slicker's. When he sold Slickcraft he had a non-compete so he went into sailboats. When that ran out he started Tiara. Tiara builds some really high end powerboats. This means that the glass work on S2's, like my 9.2A is top notch. The only poor glasswork I found on board is the relatively weak tabbing of the engine beds. Look for tabbing broken loose from them. Easy fix. Some epoxy and a few screws did the job. The tee shaped cockpit is nice and is a pretty rare find in a boat of that vintage. Decent, but not impressive performer. On par with a Catalina 30.
The 9.2A has standing head room for a 6 footer (me) which most 28's won't have. The extra two feet generally means the berths are larger. The vee berth is quite comfortable for two. The convertible dinette is a bit short and tight for two adults, but easily sleeps one. One of the surprise pluses of the removable dinette table is that in reality I have never had it mounted. We nearly always eat at the cockpit table and having the wide open cabin (without the table) has been great. Kenyon spar is fine, but check the head door and deck. The block under the compression post was either never installed or has disintegrated on many 9.2A's. If the head door doesn't hit the stop block opposite it that is a sign. Also, a shallow dent may be visible under or near the mast step. The aluminum tanks for water and fuel are also likely near the end of their service life after thirty years. No rudder problems, but stained/damaged sole in the galley may mean the rudder stuffing box needs repacking. Took me a while to figure that one out.
Dufours are reputed to be great performers but God are most of them ugly. The 29 isn't bad. Not a lot of them around. Personally I'd avoid an older Volvo engine like the plague as parts for older Volvo engines are nigh non-existent.
There is a Sabre 28 in my mooring field. My boat is significantly bigger. To be frank, I shopped 28's when I bought my 9.2A and it wasn't worth it. For the minimal increase in yard costs the extra two feet are well worth it (in my case, +2 feet = about +$130 for winter storage). The looks of the 28 may appeal to you in comparison to your old Morgan 382, but I would shoot for a Sabre 30. Build quality of Sabre's is supposed to be quite good.
You have to go aboard all the boats to shop them properly and be sure to get a survey. I had my heart set on an O'day 28 until I went aboard one and discovered that it wasn't a big enough improvement over my Lancer 25. I was upgrading and it just didn't feel like a big enough move. Headroom was lacking and peeing standing up is great (see the Lancer 25's interior to understand that desire). I was then certain I wanted a Newport 30...until my surveyor looked at a few for me and suggested I shop for a better built boat. I thought about Hunter 30's, but the few I saw really looked their age. It even took me three 9.2A's before I bought mine, but by then I knew I had the right boat...it was just a matter of finding one in good enough shape to buy.
Have you considered the Tartan 3000? Pricey compared to the others at $30K, but if you take a loan out you can deduct the interest as a second home. I do and it saves me about 3 boat payments a year. Plus I hope to sell her for at least what I paid for her. Someday. So the risk is low.