The online quant test are indeed very similar among them and hence, better to prep.
However CAREFUL, since the OW one has the fame of being the taughest one and with a lot of time pressure.
I would strongly recomment you practice it with the Integrated Reasoning part of the GMAT exam.
There are free exams in the internet that you can use for practice (the one of LBS MBA page, Verits prep, as well as some free trials for courses such as the one of The Economist (https://gmat.economist.com/)
The old McKinsey PST, Bain SOVA test, etc. are all quite similar so leverage resources across all of them.
Hope it helps!