Hello Gungoreno,
You can expect better air filtering to be more UPS intensive than air filtering for sure. The latter uses a core mechanic of the Factorio engine to remove pollution (basically producing a negative amount), which is extremely efficient. Better air filtering actually does some computations in lua to perform the 'suction' and removal of pollution, which requires more time to run.
However, the update process is highly optimized such that it scales well with the amount of filtering machines. The main contributing factor is the size of the area they cover. In larger bases you can expect more compute time needed.
That is why you can also configure the interval of updates. Increasing this should give you enough margin to take the mod all the way to the end game. Here again a clever optimization is used to spread the required computations over different game ticks to prevent stutter and help the game run smooth again.
I hope this helps!
–JoeyDP