Useful?
For me yes, for you could depend since it's a really personal thing.
I don't own the whole bundle but some Ren plugin.
Rde esser: my go to de esser (9 time out of 10 in shelving mode, and if I need to catch specific frequency I reach for the C1 and manual de essing off course).
Ren bass: don't use this so much on kick (kick I go with ton of mult), but I use it all the time on bass mult
Ren comp: I use it on every session since 2 years now. Often on kick and snare mult, some bass, pad, lead vocal or bg vocal and also acoustic piano.
This don't have "any" color so really transparent comp.
Used Ren verb on many studio, really good reverb (I don't own it, I wanted to buy it but I already have lot of reverb plugin like Dverb, reverb one, revibe and aether...).
I dig ren eq but same thing as ren verb, already own many eq.
Best thing you could do is demoing the package and make your choice after that
