I don't know anything about rubber interlocking mats, but I use industrial sheet vinyl with complete success. Very easy to clean. There is no problem with hot chips damaging it, but when I had a small mat in front of the lathe, bits of swarf would collect between mat and vinyl and stick to the mat backing. The solution was to get rid of the mat !
This is in my garage workshop. The floor consists of a DPM, 4 x 4 ft slabs of 2" thick polystyrene with a matrix of 2 x 2" battens round the perimiter and between the slabs. On top of this is flooring grade chipboard and the aforementioned industrial grade vinyl.
This system, while maybe not being the cheapest, provides a good level of inuslation and standing comfort. There is no sign of settlement under the machines (M300 lathe @ about 800 kgs and Thiel mill @ 1.25 t – among other bits and pieces). After 10 years use, I see no reason why it cannot continue for at least another 10 years.
I would agree that in an upstairs bedroom, sound insulation should be considered, especially if another dwlling is adjoined to yours or if downstairs rooms are being used while you are enjoying yourself.
Dave
The Emerald Isle