I'll preface this by saying that most of my photo work is dealing with old photos on/from film. That means lower resolution, film grain, and often physical deterioration &/or damage. IOW there's a lot to fix. I look at AI photo software with one question: "can it help me get better results?" For Aiarty Image Enhancer the answer is yes, BUT, there's better/faster alternatives. In a nutshell, if you don't want to spend any money -- those alternatives are not free -- Aiarty Image Enhancer should work passably well for you.
For digital photos the Photo model *might* help with some, but in my tests not all noise. Otherwise it could be useful for upscaling or enlarging a photo. For analog photos [film] it can help with noise or grain, but that requires using 2 different models. Aiarty Image Enhancer is also comparatively very slow, maxing out my lowly RX 6600 graphics card. AMD, Intel, & Nvidia GPUs all have their favored AI frameworks, and Aiarty Image Enhancer may make better use of Intel or Nvidia GPUs, plus higher end graphics cards have much more horsepower. When it comes to processing speed your mileage may vary.
I have not found anything to date that will actually add detail or sharpen an analog photo, though a mix of settings in Luminar Neo can give the appearance of a sharper, clearer photo in many circumstances by manipulating lightness/darkness and localized contrast. Topaz DeNoise AI, now sold as part of an AI bundle, does a better job getting rid of noise, and is magnitudes faster. Denoise in the Photo Restoration Neural Filter in Photoshop does a better job reducing film grain, & is much faster, while the non-AI noise removal in the Camera Raw filter can help reduce the appearance of grain in some situations when turned up to 55 or more, and is almost instant.
The ImageEnhancer folder takes up ~475MB. The models it downloads are stored in the ProgramData\ Aiarty\ folder, and in my testing were smaller than those used by Aiarty's Image Matting. Models for both can be deleted when you're done using them to save space. By default one of Microsoft's C/C++ runtime libraries is installed, though if you installed Image Matting earlier Image Enhancer installation may recognize it's already installed and skip it. New registry entries are minimal.
Note: SOS is currently offering lifetime license SoftOrbits Photo StampRemovel 16 with AI as a giveaway