In FP1 Lewis reported some brake issues then went to the pits just to change them. Bottas had a DRS flap failure at the end of the session, prior to staying longer in the pits due to some back-to-back tests on the new and old 3rd damper ...
Then in FP2, according to Toto, they were struggling to put the balance on the car and the reason was that the tyres were not in the right window. Anyway, as Ant said on Sky they don`t look so good over a hot lap and he thinks that is presumably to carrying more fuel than the opposition ... To me, it seems that they are working on that new rumoured updates they`ll bring at Suzuka ...
Regarding race pace, in FP1 on the M tyres, they were on a par with Ferrari and VER both on the S tyre!
Then in FP2 VER was ahead of everybody both on S and M tyres.
Ferrari were splitting their workload with Charles being almost on par him, doing very consistent mid 1:39 on the S tyres, and just simulated what I think Merc are trying to do: the first stint on M tyres and the second one on the S ones. We have to keep in mind that we just had some 28 degrees Celsius on track when they did those sim laps which could the final race stint. VET was settings times which were a couple of tenths slower but he was also very consistent too on the M tyre.
And least but not last Merc: some scruffy laps from Lewis until the end when they show us a glimpse of what can they do, particularly on Bottas` case. My perception is that Lewis was simulating the last phase of the race on the S tyre and he was doing laps constantly on a low 1:40 as he was instructed to do so in order to stretch that stint as long as he could ...