I've been trying out a few brands/lines including W&N S7, Broken Toad, Rosemary & Co, W&N Galeria among others. I'm still finding my feet after coming back to the hobby about a year ago so my opinion might not count for much but my personal favourite is, perhaps unsurprisingly, is the S7.
A bit more of a surprise though is how good the Galeria brushes are for water soluble oils (they are an acrylic brush after all). They are quite stiff and work quite well with the more viscous oil paint and are brilliant for applying the initial blocks of colour before switching to S7 brushes for finer work. I especially like the filberts in the range, brilliant for scrub coats. One downside of the Galeria brushes are that the flats (or one stroke) brushes tend to curl up at the ends fairly quickly, they become sort of hook-shaped. However, they are cheap as chips so I just nip down to The Range and get a few when I need them but to be honest I find myself using the filberts more nowadays anyway so not much of an issue for me.
I found the Broken Toad and Rosemary & Co brushes to be virtually identical. So much so in fact that I've concluded that the Broken Toad brushes might even be rebranded R&C brushes. They are good quality brushes but I found the bristles to be a bit too long and too bendy for me and the points, while good to begin with, split quite quickly in my case. I know that others rave about these brushes but for me they just didn't work out, it just goes to show that brushes are a personal thing.