Although it is far from ever replacing Photoshop, it is a strong contender for an affordable and highly specified photo-editing suite. As I have PS/CC, Studio is an interesting software package for its streamlined flow and the integrated UI so that you do not have to go to the enormous and energy-sapping trouble of opening plugins one after another and again and again... which is nice.
In its own filters, it uses the powerful Topazlabs 'engine' which drives all the effects behind each individual plugin. This is a nice shorthand palette to brush and mask with some complexity - and view snapshots of each developmental stage - to mix and match the old, familiar surfaces and textures of Topazlabs Plugins.
That it is a viable alternative to PS/CC is indeed testimony to its ample power and sophistication (although it doesn't allow focus stacking). Welcome to the 21st Century Topazlabs!