I use Photoshop.
Partly it is what you are used to. I started using Photoshop before Lightroom was available and stuck with it, because for my workflow it is easier and faster and more flexible.
I use Smart Objects - a lot. If you make multiple rountrips from Camera Raw to Photoshop with multiple smart object layers only the first layer can be processed in Lightroom, every subsequent layer must be opened in camera raw, so I see no advantage to starting out in Lightroom. it just adds a second interface that I don't need. Since camera raw and Lightroom do the exact same things I have found it easier to use photoshop and camera raw.
More detail - Let's say I've shot a portrait of three people. One is very fair skinned, one medium and one is African-American. In camera raw I'll first adjust the exposure for the main subject and then send the file to Photoshop as a smart object. In Photoshop I'll make a couple of new smart objects from that original layer. I can double click on one of the smart objects and be back in camera raw to optimize the exposure for the second person. Return to photoshop and thendo the same with the third layer for the third subject. Back in photoshop I use layer masks to blend the three layers together into a single image that is perfectly exposed for each subject . And since I've used layer masks and smart objects I can go back at any time and tweak a layer or even make a new smart object to adjust something else inthe picture .
I used multiple smart object layers on probably 90 percent of my photos - adjusting exposures for individual areas of the photo. I'll optimize one layer for the sky and another for the foreground and the used layer masks and the paintbrush tool to combine the layers.
Some people say photoshop is destructive and Lightroom isn't, but that's only if you don't know how to use photoshop. As long as you use layer masks and create new layers along the way, you have the ability not only to go back, but you can turn specific changes on and off or rearrange the order anytime you want. That means you can go back six months later, look at every step you used and adjust any step if you want to do something a little different.
I know some people swear by Lightroom. Me, I found myself mostly swearing at it. I didn't like the way it catalogued files and since the exact same development tools and settings are available in camera raw - plus the flexibility to use layers in photoshop, I've found photoshop is just a better interface for me.