I love my Maddison, it's perfect for me and my family (kids are 4,5 and 7). It has a vast amount of internal space, plus enclosable annex, plus additional annex off that - wet weather is no issue for us at all.
Having said that I was set on getting a Trackabout due to its known quality and unmatched aftermarket support.
Trackabouts weigh more than Jimboombas so that was one factor to consider for me - 3 litre Patrols aren't the most powerful tugs around. I also wanted a walk-up to the bed, both for the additional tent size and for the convenience - I wouldn't have a CT without it. I also like the look of the Jimboomba because I prefer something that looks like a dedicated recreational trailer, rather than the more conventional box trailer look - although of the latter, the Trackabout is one of the best looking box trailer styles.
You really need to make a list of what you need, then tack on what you want, then compare what you get from the manufacturers.