Unreliable

Both of the claim is incorrect.
It neither affects website speed – only implements the functionality when Administrator is viewing (so, no affect on general website or visitors),
and neither it provides unreliable data – I don’t if you can find (if you will, let me know) that provides such in-detail functionality and data (and whatever it is unreliable, it says).

However, there are such occasion, when getting 1-star feedback for nothing. no problem, good luck.