samsung ssd uses tlc

crucial SSD uses mlc. MLC is better than TLC. The negative aspects of MLC are amplified with TLC, but TLC benefits from higher storage density and lower cost. Also, depending on the chipset inside, different SSD can only maximizes its potential at different capacity. The sweet spot for last generation SSD is 256gb and up. Current generation SSD are usual better with capacity 512gb and up.

Using the operative system hard drive to store disk image/backup is a bad idea. You are better off storing them on a NAS or a portable drive. If you have high bandwidth internet(fiber optic/giganetwork), you can do off site backup. You can recover your files even if fire/flood destroyed your house. For most people, I would recommend NAS. A cheap alternative to a dedicated NAS is getting one of those newer routers (e.g. ASUS RT-AC68u) which supports USB 3.0 storage.  Hooking up a USB 3.0 drive to the router will allow the combo to act as a NAS (of course no raid and other enhanced features). A 5 terabytes, USB 3.0 external desktop hard drive can be bought for less than $150. In the event of a emergency, all you need to is grab the drive and run.