This show is all over the place in terms of writing and tone. It starts out fairly grounded: a group of survivors have to make tough decisions to make it in a vampire-infested post apocalypse. The characters are interesting for the most part, although the main character Vanessa is by far the least likeable, though she gets a bit better by season 3/4. The show has a lot of good practical gore effects as well, although I think in the universe of Van Helsing people don't have spines because it is RIDICULOUSLY easy to cut off someone's head in this show, lol.
The show started to lose me in seasons 3/4, however. It seems like the show got more of a budget for season 4 so they started using more bad CGI and adding pointless side locations and characters for no real reason other than because they could. Also, after all the build up of the Dark One, when you actually see it, it is soooo underwhelming. The vampires in the first two seasons (Dimitri and Aleera) were far more terrifying than the campy ones that are in the later seasons. There's a lot more tension in general in the first two seasons, by the second season you're pretty much never worried about the main characters for reasons which will become apparent if you watch. Also, the show just basically replaces the two main characters with younger versions in season 4 because why not?
As for if I'd recommend it, maybe watch the first season a bit. If you like the main characters then maybe give it a go, if not I wouldn't bother.
