It's good that we have choices, I guess. Try each and use the one which feels most natural to you.
For me, that's Aperture. LR feels like banging my head on a brick wall every time I do battle with the UI. Modal program operation is something I remember being told was a bad thing back when I was a computer programmer- 25 years ago. I really
dislike the way that keyboard shortcuts change meaning from module to module.
It's just my opinion, but I'm the one who has to spend several days a week in this application, so I need the UI to work with me.
Some will say LR encourages a methodical workflow. Personally, I think keyboard shortcuts that change from mode to mode is bad UI design.
If I spot a dust spot that needs fixing, I want to press 'x' and do it right now. Whether I am about to print the picture or organising my metadata. I don't want the program to tell me I can't do it until I press some other button first.
Aperture also has the best retouching tools for my particular purpose: skin smoothing and clone/repair.
Aperture has shortcomings: its image processing engine has a fairly quirky interpretation of Hasselblad RAW files, which isn't ideal. I gather LR has the Hasselblad colour profiles from Phocus built-in. So I end up doing an insane procedure of one-light grade colour pass in Phocus, export to TiFF, fine tune and retouch in Aperture. Which someone is bound to point out is also modal in its way since I'm using two different programs, to which I'll agree. On Canon and Panasonic files, Aperture does just great. And sometimes the Aperture colour correction is a nicer starting point than the Phocus, so I always import both into Aperture and start from whichever I like best.
I'm also tired of the fact that C1 doesn't support arch-enemy Hasselblad's files, or Hasselblad won't licence to arch-enemy C1, or whatever. I don't care- be grown-ups and support each other's cameras!
But the main thing is that the UI of Aperture (and most other Apple interfaces eg FCP-X) was designed by someone who thinks like I do and works like I do.
The LR interface was designed by someone who clearly thinks very differently from me, and I plain don't get on with it. Same is true of most Adobe products. To my eyes Adobe interfaces are often scattered with microscopic hieroglyphic buttons of indecipherable function, some of which can conceal flyout triangles about 0.5mm wide on my 30" screen (hard to hit reliably with a graphics tablet pen) which in turn reveal a whole row of additional indecipherable functions.
And you can't just use a keyboard shortcut, because that shortcut probably doesn't work in the mode you're currently in and will end up doing something completely different that you didn't want to do because the program thinks trying to do what you want to do right now is CRAZY TALK.
I agree with previous posters- my hope for Aperture 4 would be LR's processing engine (with manufacturers profiles integrated) with Aperture's interface. About the only functionality missing for me is vector-style gradients and smart fill for local adjustments- doing it by hand with a paintbrush is fine for a lot of things but impossible to do smooth transitions.