I can only speak for my local one, but I think they're all pretty similar/of the same standard. I would describe Thegym as a cardio bunny/DYEL gym.
The dumbbells only go up to 30kg
There aren't many 20g plates
The free weight section is tiny (it's a real pain because of how busy it always is)
The equipment is very limited. Handful of benches, no bench station, only one power rack and only one proper barbell.
It depends what you want from the gym? If you want to 'lift properly', Thegym is an awful choice. If you want to just go every now and again, do some cardio and use a few cable machines, then it's a decent enough gym.
I will just add, in my experience a LOT of douches go there (there are obviously perfectly pleasant people too, but there are a lot of douches) . If you get annoyed easily by people leaving the gym in a mess/not putting weights back, standing around chatting all day and just generally being little ****ing ****s, it's probably not the place for you.