We have been using 240 and 112 in the teaching studio with commercial glazes (purchased powdered) in 5 gallon pails for about 5 years, firing in a vented electric kiln to cone 5 tip touching. This cone suits the glazes we use, many of which will begin to overfire at cone 6. We have not tried the 630 clay body.
At cone 5, none of the Standard white bodies (aside from 630 which I have not tried) are truly mature. If the glaze is not tightly sealed, the clay body can absorb enough water to ruin your grandmother's antique dining table. We have run into a couple of glazes recommended at cone 5 which did not prevent seepage. I struggle with even using the clay in the studio, but our adult students love the feel and the fired results, so we march on. (Until very recently, Standard was our only easily available clay so we had little choice. Now, all the test tiles are made!) At cone 6, you will likely find more reliable results, but beware uneven kiln temperatures. I have also tried all of the white Standard bodies which include cone 6 ranging up to cone 10, none of which were remotely satisfactory at cone 5-6. A Standard tech once told me that my personal standard for clay body maturity seemed to run around 4% absorption or less, but the industry standard for stoneware begins at a higher absorption rate.
The 240 is less forgiving re: warping and cracking, especially if it's too thick, if there is large variation in wall thickness within the pot, or if it has not been well compressed, but you have the experience to deal with that. Surprisingly, children's work is LESS likely to have problems than adult's work, probably because they're working smaller and getting more one-on-one tutelage plus the benefit of the instructor determining how their work dries, etc. The 240 provides an excellent background for commercial underglazes. As an aside, the speckles in the 112 do show through many commercial underglazes. Also, the two bodies are similar in shrinkage/absorption and recent experimental agateware shows promising results, but the jury is still out!
Re: using the same glazes on the 240 and the 112, all of our glazes will work on both although some are more aesthetically pleasing on one body. Consistently, glazes are MORE prone to running on the 240, especially in layering glazes or thicker applications. I have found this to be the case on all mid-range white clay bodies. Going back to the clay body maturity issue, the glazes that allowed water seepage on the 240 did not have any problems on the 112. Anticipating the question...yes, glazes, especially transparent ones, are more likely to craze on the 240.
Finally, recycling 240 and 112 scrap together results in a lovely light tan body with speckles that is great to use. Glazes results are very similar to those on 112.