I use both the programs you mention and in the main they both work well however occasionally they both screw up so always create a restore point before using them. The drivers I have found to be careful of are the AMD video ones so I never install them automatically, I do it as a separate operation after installing all the others first.
I also had a problem once with the AHCI driver on just one machine out of 10.
best advice in my book, set up a favourites folder with links to your laptop or motherboard drivers website and get drivers from there, and one for your graphics, printer drivers from the makers webs etc.
Just to even up the discussion I just did a reinstall from scratch on one of my laptops. After installing everything including MS updates and all the programs I took a disk image before using Slim Drivers and IOBit Driver Booster. I used the Slim Diver program to update everything and then the IOBit to update the couple that Slim Drivers had not found. Afterwards the laptop booted no problem so I have now taken another Disk Image to replace the previous one.
No program is ever perfect but so long as you take sensible precautions ie backup first, these 2 programs do save lots of time.
I think Jock1e OD'ed on his paranoia pills this morning...
But back to the topic: while I understand the rationale for backing up your drivers in case you need to reinstall them, I'll never understand those who feel they always have to have the latest version of their drivers just for the sake of having the latest version. By all means, if you know that a new version of a driver gives you reliability, functionality or performance you currently don't have and need, then by all means go for it - but if there's one guaranteed way of screwing up a perfectly good, working system, it's arbitrarily updating the drivers for no good reason.