/.jp の記事 より。おぉ、大英断!

Now that the install sets are included in the installXY.iso image file, the single ISO file can be downloaded for the installation process. Previously with the cdXY.iso image files, you would also need to download the install sets separately (either to a local mirror or during the installation). This may have caused problems if you were setting up a system without network access during installation.

New Installation ISO Files in 4.2

FreeBSD に慣れすぎちゃって*1 OpenBSD はほとんど触ってないのですが、これを機会に再チャレンジしようかな。

*1:なんせ 2.0R(98) が最初ですから...