I've used a lot of Windows and Mac audio software over the past 13
years. But, I am not at all into looping and use very little midi or
virtual instruments. So for real audio recording with very good built
in EQ's and compressors my favorite is Sawstudio. It installs in
seconds and is a solid code. There is a X-mas sale on now and the Basic
version is $200. However, you would have to buy an additional bit of
software to use midi at all.
Reaper is also painless to install and is solid and $60.
For virtual creativity (and sounds) check out Propellerhead's Reason
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