Glad I could contribute something.
If you want more tips: Choose the channel that suites you best. If you like arch, you probably like rolling distros. You could skip the stable channel and go for testing or unstable and that’d provide you with an experience alike a rolling release model. That isn’t officially supported… Debian focuses on getting security patches into stable, not necessarily the other channels. That’s why only stable is recommended. However, the other ones work great and Debian usually do a good job with keeping them well-maintained, too. I run testing on my laptop and I like it.
(Edit: And Debian should have a good amount of customizability… You can (re-)configure the package manager not to install recommended or suggested packages, and you can also skip the manpages and documentation if all you want is a small system.)
Not under normal circumstances. I had some issues recovering damaged harddisks that had lots of errors and retries and sometimes either the USB adapter or the mainboard SATA would crap out or handle it better. But for normal copying of HDDs, both should copy the exact same data.