I've got PollyScale bottles that I've had for years, and they certainly seem to be good as new. I know Floquil's shelf life has a good reputation among model railroaders, but I haven't had much experience with it myself.
I became a convert to acrylics about thirty-five years ago, when the original PolyS came out. In the hobby shop where I was working at the time (in Columbus, Ohio), it initially didn't sell. There were rumors (totally false) that dried acrylic paint would come off if the model got a drop of water on it, or that it would rub off. The owner of the shop finally got fed up and told me I could take the whole PolyS rack home with me for free. I started experimenting with it, and discovered that, though it required a somewhat different technique than the enamels I'd been using for many years, it was capable of producing excellent results when brushed. (I've never enjoyed airbrush painting much. I have an airbrush, but I scarcely ever use it.) Then I noticed that, whereas up till then I'd generally worked on a model for a couple of hours at a sitting, I was finding myself staying in the workshop for four or five hours at a stretch. I suddenly realized that was because the enamel (and paint thinner) fumes were gone. I've been an acrylic fan ever since. (And when PolyS started making colors specifically for aircraft and armor, the boss started stocking it again. I talked quite a few customers into using it. I never heard from one who was disappointed with it.)
I remember vividly when Testor started making its glue "unsniffable." My recollection is that initially it put oil of mustard into the mix. Testor put out a big package of press releases for hobby shop owners to send to their local government officials, many of whom had been talking about banning glue sales to kids under eighteen. My boss sent such a package to a member of the Columbus City Council. Kids, unfortunately, didn't read the press releases. We had several raunchy little brats who came in wanting to buy eight or ten tubes at a time; we knew perfectly well what they were doing with it. Whether it actually had the effect of making them high or not I don't know. The company literature said they'd throw up before they reached that point. (The boss took the position that Testor was telling the truth, the kids weren't actually getting high, and if they were it wasn't his problem. When he wasn't around, I quietly made it my personal policy never to sell a kid more than one tube at a time - even when he claimed, "hey man, I'm working on this really big model." Yeah, right.)
The oil of mustard (or whatever it was) also had the effect of making the glue stiffer and stringier. I switched over to Revell and/or Ambroid for tube styrene cement. Both those brands are gone now. (There was another one called Ross that I also liked - also gone.) Come to think of it, maybe those brands were slightly hallucinogenic too. That might explain the state of my brain lo these many years later. (My wife says that, though I don't have Alzheimer's, I do have a bad case of Halfzeimer's. I say she's got the other half. Our screwy old cat, Yehudi, clearly has Catzheimer's.)
I usually use the liquid stuff nowadays, but I still keep a tube of Testor's handy. I contend that, especially in ship modeling, there are times when putting a drop of tube glue on a part is the best way to stick it to the model. I wish the good ol' Revell Type S or Ambroid plastic cement was still on the market.
As for paint, I'd urge ship, aircraft, armor, and figure enthusiasts to check out the Vallejo line. It's enormous, and the paint seems to handle just about like PollyScale. Modern warship modelers should take a look at the Lifecolor range. I bought two sets of U.S. WWII warship colors from that company, and I really like them.
For model railroaders - well, the world is coming to an end.