Planetary/lunar - 600d live feed v ZWO ASI120MC or similar

[runoffshed]

I am not a very experienced imager and would like some advice please.  

I have recently been using Backyard EOS to take the live feed off my Canon 600d with the 5x setting within the software to obtain what I have read is a close approximation to a 1:1 pixel image.  I have only tried the Moon and Jupiter so far, both in quite poor conditions, but the results were pleasing.

My question is, how would the images I can obtain this way compare to a low end dedicated camera like the popular ZWO ASI 120mc?  Is it a worthwhile upgrade or would it be better to hold off and save for a much better dedicated planetary camera?

I have looked around the web and although I can find images obtained in both these ways it is hard to compare them as the scopes/locations/imager are always different.  Jerry Lodriguss wrote a great article in Sky and Telescope about using a DSLR for imaging planets using movie crop mode or equivalent and has produced stunning images but he is using a C11 and doesn't mention comparisons with specific cameras etc...

If anyone has tried both or has any ideas I would really appreciate the advice.

Many thanks

John