I found this app to be surprisingly useful, and the price was great in the Smart & Tidy bundle. For boring reasons I needed Tidy Up and found it really useful before, so Smart Trash was a nice addition that proved better than I thought. I accidentally updated a program that only told me after the fact that it was a paid upgrade, so now I only had it for a few days. While it was installing I deleted a program that I was pretty sure contained adware (yay for multi-tasking) so I wanted to delete that immediately while the installer was still running, but I wanted to leave the older version which the update had placed in the Trash so that I could restore it after deleting the update. Smart Trash worked just fine. Yeah, I could have called up the Terminal and deleted the file that way, but it's a lot more work for a simple operation. And yes, it's a rare situation but as a reviewer "rare" situations seem to popup a lot, not just that one.
It might have been timing that I needed both apps that MacUpdate put in the mini-bundle, and often the bundles don't interest me, but when they come up with ones that I need right at the moment and the price is right, it makes my day. I know that it's easy to rack up a big bill buying "interesting" apps even at $10-15 each, but I've finally learned to sleep on it unless the software is a no-brainer like this one was for me at the time. I'm giving it 5 stars because it answered an immediate need and worked. I have NOT test the whole thing and I appreciate reading the other reviews that point out bugs. I will update this review if I find any later on.