Building a system these days is not that hard; you may run into a few issues with clearance (GPU, heatsink etc.), but for the most part things are pretty simple. The P55 Extreme4 was like that. The hardware was no trouble getting in place while the installation of the OS was a snap. Oddly, though, there was no Windows 7 driver for the LAN chip. We had to wait until we ran the driver installer to get all of that going. Once we did, things moved right along.
As we talked about when we looked at the box, ASRock has listed quite a bundle. When we took the time to look at things, it was not as great as it seemed. Much of it was trial versions of software or very light free versions. It was not overly impressive to be honest. There was also nothing about how to get the software to use your iPhone as a game controller.
There was some free software that ASRock did include. One piece of software that you may want to install is the IES (Intelligent Energy Saver). This software is capable of dynamically controlling the power in use by switching back the power phases. It can help reduce the power draw at idle state while still allowing for full power when you need it.
Another piece of software that while interesting, might only be of use to a few people; that is the Instant Boot software. This piece of software allows you to put the system into an advanced sleep state so that when you hit the power button it instantly awakens for fast usage. Personally, I do not like to do this as I have seen many applications that will fail upon a resume like this.