Windows 7: Image your system with free Macrium

You will still never truly know until you do it yourself. There may be some quirk about your system that is different.
Since you are building your own system you are going to get grease under your fingernails so buy a spare $50 spinning drive and put all your imaging options under test. If you cannot recover your image to a blank HDD don't use that particular imaging software.
I suggest you try the new free Easeus imaging product as well.

Looks Good.

Had to restore from back up. Worked great, real life saver. Macrium is awesome.

I have backed up my "C" drive with Macrium and found the compression to be quite good. I wanted to try backing up my portable hard drive to another portable hard drive, I backed up 300gb of data and the image produced was 290gb, I wonder why the compression was virtually none? I didn't alter any of the backup settings, left it all on default.

The amount of compression you get is very dependent on the type of data you are backing up. If you are backing up pictures, music and videos you will not get much compression as these are already highly compressed.

Yea, I was mostly backing up that stuff, thanks.

It is. The first time I used it I was amazed at how fast it was, too.

I've just given EaseUS Free a try. I have to say I'm impressed. It is considerably fuller featured than Macrium Free EaseUS backup software comparison: choose the best backup solution for your data and system.

If you install the WAIK you can create a PE recovery disk which works nicely under YUMI. On the whole the interface is a lot less confusing for new users.

Two points on EaseUS after a days testing compared to Macrium. An image of the System and C partitions used for the test. A total of 71GB of files.

1. Macrium is considerably faster than EaseUS. 29min vs 50min.
2. Macrium creates much smaller files than EaseUS. 30GB vs 48GB. Both at default compression settings.

The smaller size could go some way to explaining the difference in time as I am backing up to a USB HDD and the speed of this seems to be a limiting factor.

As you said, the HDD speed is certainly a limiting factor. But more compression needs more CPU. So that could play a role in favor of EaseUS. Maybe you can make a comparison imaging to an internal HDD.

But then again, a different configuration (slower CPU, faster disk, etc.) may yield different results. I run my images in the background. So length of time is not a big deal.