MRETramp

I'm interested in Express Burn Plus, Wavepad, etc, so I have gone to the Buy Software page on the nch site. The bundled options are attractive. However, the price seems to vary depending on the computer that I use when accessing the site. It's US$34.20 (50% discount) from most of the computers that I use, but when I access from my laptop (where I would install the software), the cost is US$47 (30% discount). I can't find any other way to ask about this, other than to post on one of the forums.