Upgrading to silicone heat bed, will it burn my house down?
The heated bed port on your board has a 11A fuse. It will not work for a heated bed requiring 16A of current, no matter how good the MOSFETs might be. Note that the terminal block might also not be rated for that much current. You'd have to check, because often it is not the MOSFET itself that catches fire but the wiring or terminal blocks.

Also, keep in mind RAMPS only drives the gate with 5V. The value specified in the datasheet (for 10V) plus 20% is probably a bit optimistic. The datasheet doesn't specify the resistance at 5V, so you're guessing at what the resistance might be. Since you're already running the part quite close to its limits, and considering ambient temperature might rise above 25C, I'd be cautious. The designers of that board only intended it for use at 11A, probably with good reason...