There are a number of oddities with SCP-914 listed as follows:
1. If you put a Medkit into 914 on Rough or Coarse, it will remain in the input slot, and the output appears to get a copy of the last-used decal.
2. It appears, from looking at Items.bb, that 914 is supposed to be able to create the Heavy Bulletproof Vest and the Bulky Bulletproof Vest out of the Bulletproof Vest (put through on fine or very fine), and according to the wiki it fails because it is bugged. I'm not sure if this is accurate or not.
3. There appears to be a "Mysterious Hazard Suit" in the items.bb file, which looks as if it would be a 914 upgrade to the Hazard Suit. I'm not sure if 914 is supposed to be able to spawn it or not.
4. This really isn't a bug so much as a suggestion, but when you put an 18V battery in on 1:1 it outputs... the same thing you just put in, in this case the 18V battery. Same with the Blue First Aid Kit, the S-Nav Navigator (red text version, which has no 300 in it's name), and the RedVision Eyedrops. These should instead convert the item back to it's original state, as the 9V battery, the First Aid Kit, the S-Nav 300 Navigator, and the ReVision Eyedrops, respectively.