Well, maybe I haven't given the stuff a fair trial. Or maybe it boils down to a matter of what one's used to using.
Testor's "Non-Toxic," if I remember correctly (always a questionable proposition these days) was introduced in the late seventies or thereabouts, in response to complaints that kids were buying the "normal" Testor's Plastic Cement (in the orange tube) for sniffing purposes rather than for building models (which was undoubtedly true).
Prior to that time there had only been one form of Testor's Plastic Cement in a tube. I remember it as being packaged in a yellowish cream-colored tube, for the traditional price of a dime. (There was also the bottled stuff - with the little brush in the cap - but that was more expensive and, in the eyes of an eight-year-old, messier. One had to instruct one's mother quite carefully to be sure to get the tube that said "plastic cement," rather than "model cement." The latter was the faster-drying of Testor's two forms of adhesive for balsa wood - the slower kind being in a white tube.) I was working in a hobby shop when the glue-sniffing craze hit (or, I guess I should say, when it started attracting major public attention). As I remember it, Testor's came up with two responses. It announced, with great fanfare, that it was adding something called oil of mustard to its standard (orange tube) plastic cement; the promotional literature claimed that sniffing it would make a kid throw up before it made him high. (The company sent boxes of glossy pamphlets to hobby shop operators, for distribution to concerned citizens and government officials. My boss mailed a stack to a local city councilwoman, who'd been making noises about regulating the sale of glue to kids.) Apparetly the concerned public didn't buy Testor's claim that orange tube was unsniffable. (I can honestly say that I have no idea whether the claim was accurate or not. I do know that several of our younger patrons bought large quantities of it, obviously for sniffing purposes, until I threatened to sick my faithful dog, Harvey Wallbanger, on them.) Shortly thereafter came the appearance of Testor's "non-toxic" plastic cement, in the blue tube with the lemon smell.
The patrons of the store where I worked (many of whom, of course, were committed "liquid cement" users anyway) were thoroughly disgusted with both products. The addition of the oil of mustard made the old reliable orange tube thicker and stringier. Blue tube seemed to be less stringy, all right, but it didn't seem to stick as well as its competitors. It also seemed to dry faster. That, of course, can be an advantage or a disadvantage, depending on the circumstances.
At any rate, the shop where I worked continued to stock three other brands of tube-type plastic cement: Revell, Ambroid, and Ross. Those were the ones most serious adult modelers bought. I always found their consistency and performance superior. (I especially liked the Ross brand - which I haven't seen for many years.)
A few months ago I happened to have reason to stick some pieces of styrene strip to some basswood - clearly a job for tube-type plastic cement. Knowing there was no hope of finding any of my old favorites, I went on a search for Testor's orange tube, figuring anyplace that sold plastic kits would carry it. I got a shock: in the thriving metropolis of Greenville, North Carolina precisely two stores, Wal-Mart and Michael's Arts and Crafts, were selling plastic kits, and neither of them had Testor's tube glue. The next weekend my wife and I took a trip to Raleigh, and I went to a Hungate's store. (Hungate's, for the benefit of the uninitiated, is a rather large chain that sells toys, crafts, and hobbies. It used to be a pretty good source for plastic kits, though it's slipped lately.) The clerk knew what Testor's plastic cement was, but the store was out of it. So I went to a genuine hobby shop - the only one in Raleigh that, so far as I know, is still in business. The guy in this one knew the difference between blue tube and orange tube, but only had blue tube in stock. (At this point I started to suspect that Civilization As We Know It was coming to an end.) So I bought a blue tube.
It didn't work. Admittedly this particular application was an unusual one - and hardly what Testor's had in mind: sticking a series of short styrene strips to a piece of basswood. But my usual, primitive technique - smearing a little glue on the plastic and scrunching it up against the wood - just didn't work. The glue justdidn't dissolve the styrene enough to make the bond.
At that point I made a pilgrimage to Wilson, a medium-sized town about 35 miles from home that is blessed with a first-rate hobby shop catering primarily to model railroaders. (It practically got wiped out by Hurricane Floyd in 1999, but has just about recovered now.) I was hoping against hope that it might have one of the old brands from the Goode Olde Dayes. No luck - but it did sell me a Testor's orange tube. Just as I remembered, it was stringy and smelly; just not as nice to work with as the old Revell, Ambroid, or Ross products. But it did stick. At least the joints in question have lasted a couple of months now. The blue tube went in the trash.
As I said, I probably didn't give the blue tube a fair chance; it may work fine for styrene-to-styrene joints. On the strength of Bill's recommendation, next time I'm actually working on a plastic kit I'll give it a shot.