Apple always overcharged for everything, which is one of the reasons the company got into such financial trouble. Ordinary mortals could not afford to buy their machines/ software. Things are a good deal better today, though there is still a residual expectation that the brand is worth perhaps 20% of the price ("worth" here meaning, of course, what people are prepared to pay).
On the question of heat, I would say that in general, 68030 PBs ran cool, though the earliest colour machines were hot. By the 270c, however, those heat problems associated with the graphics had been dealt with, as it is a very cool-running machine. The 540c runs hotter than a 270c, as does a 190cs and a 280c.
603 PBs come in two main flavours: there was the 603e and the 603ev CPU (in the 2400c and 3400c; not sure about the 1400 series). The 603e @100MHz in my 2300c runs reasonably hot, hotter than the 603ev @180MHz in my 2400c. Presumably a 3400c @ 240MHz would run hotter, but I have never had one of those to test.
On the question of heat, I would say that in general, 68030 PBs ran cool, though the earliest colour machines were hot. By the 270c, however, those heat problems associated with the graphics had been dealt with, as it is a very cool-running machine. The 540c runs hotter than a 270c, as does a 190cs and a 280c.
603 PBs come in two main flavours: there was the 603e and the 603ev CPU (in the 2400c and 3400c; not sure about the 1400 series). The 603e @100MHz in my 2300c runs reasonably hot, hotter than the 603ev @180MHz in my 2400c. Presumably a 3400c @ 240MHz would run hotter, but I have never had one of those to test.