I found an interesting 1934 advertisement for the GEM one-piece open comb Micromatic, highlighting some of the key selling points of the razor when compared to other and presumably inferior shaving utensils.

• Holds the blade secure – five points of contact – so it can use a blade sharp enough to control any beard!
• Designed to force the user to get a close shave, by making the user lay the cap flat against the face – which, by the way, is one reason I sometimes recommend a GEM to a new shaver over a Double Edge; the angle is easier to get right
• Thicker and more rigid blades! Interestingly enough the Micromatic appeared around the time Gillette switched from older, thicker blades to the thinner blades we know today.
• Cheaper then other razors – allegedly ten million had switched to GEMs since the Great Depression, thus proving that GEMs were cheaper and better.

In addition to the offer of an gold plated Micromatic and an unspecified amount of blades for one dollar (about 20USD today), the advertisement tells us that a single quarter would get you a testing set of one non-gold razor, one single- and one double-edged¹ blade. Pretty good value, and I suspect the 25 cent razor would last a long time too as long as you bought blades.

1. See “The invention of the modern GEM blade, with two interesting variations” and “The double edged single edged blade” for more on the double edged blades for a single edge razor – the advertisement from 1934 proves they were sold earlier and thus for longer than I was previously led to believe.