As I explore migrating all my systems to Linux, I've decided to use 3 choices for my evaluation: Red Hat Enterprise Linux 5, Ubuntu 8.04 Server, and OpenSUSE 10.3. I'll be scoring them as I go along, and will ultimately stick with one that scores highest in my experience. My setup will be a system with 3 hard drives. The intent is to install all 3 OSes on this system, multi-booted.
Download experience: If you hope to just download RedHat's Linux from their site, you'll be frustrated to learn you need a subscription to get a basic ISO image. You'll also be tossed back and forth from the Fedora site to their JBoss stack site. This nudging is annoying - for an OS I believe is basically free. It's much more straightforward with Ubuntu and OpenSUSE - download links give you what you need. [RH=0, S=1, U=1].
Install media: RHEL5 comes on 6 CDs, although you may need only 2 or 3 for a basic install, depending on options selected. Ubuntu is 1 CD as is SUSE. The less the media needed for a reasonable install, the better. [RH=0, S=1, U=1].
Install experience: I felt a bit skeptical working with Ubuntu - it reminded me of text mode installs on Windows NT 3.11. It does a good job detecting hardware though and installs faster than the other 2. RedHat takes the longest - up to 40 minutes. I felt most confident about SUSE and had an install in 25 minutes. Another dimmer for Ubuntu - it failed to detect an existing RHEL5 install and configure GRUB appropriately. When I pulled the drive with RHEL5, Ubuntu failed to boot. It's rescue mode saved the day nevertheless, but it scores low for this small issue. I even managed to get the famous "Error 22" after installing Ubuntu. Smoothest and most intelligent install is SUSE, although I also liked how easy and straight-forward the RedHat install went. [RH=1, S=1, U=0].
At this point, OpenSUSE is looking very likeable. Ubuntu follows a close second, after which RHEL5 is just painful. I'm scratching the setup and reinstalling all 3 in this order: Ubuntu -> Redhat -> Suse. I thought of using the recently released Fedora 9, but that's 6 *.iso I have to download and burn to CD, and as long as it's some Redhat clone, I can live with RHEL5 for this experiement.
Final score: OpenSUSE=3, Ubuntu=2, RedHat Enterprise Linux=1.