I also say buy a few and see how you go. Sometimes brands have ‘newborn starter packs’ which often go on sale, usually something like 2 bigger bottles and 2 smaller bottles and maybe an extra something (a bottle brush for instance), and you can pick them up for £15ish or less in a sale. Alternatively ignore the big packs (with like 10 bottles, a steriliser etc) and just buy plain packs of bottles. Much cheaper.
For instance, this time around (DC3) we’re trying Tommee Tippee closer to nature. They’re very common around here so I’ve known other parents using them who found them easy to clean, assemble and baby got on fine with them. I bought 6 bottles on Amazon for £12.99. Hopefully they’ll be fine, but if not we can try something else.
For DC1 we used Philips Avent which were fine, they were a ‘natural’ one as well (designed to be more breast-like, in a bottle way anyway) but I find the Avent bottles aren’t as commonly available or promoted these days.
With DC2 we tried a Mothercare one which was also a ‘natural’ one, again fine (and again they don’t seem to exist anymore!).
I originally thought of getting Mam as it’s so raved about, until a relative got them. There seemed to be several parts to put together and she got fed up and bought some regular bottles; one of my friends tried Dr Brown and felt the same, great for anti colic but a faff if you don’t need it. As she put it, you really don’t want to add more hassle than necessary when making a bottle in the middle of the night - I figured she had a point!
So I would suggest buying a fairly simple bottle that is readily available/popular (like Tomme Tippee, or whatever else people are buying, as I said that seems to be the main one around here but might be different elsewhere), and if you have any issues like colic then explore the specific bottles for that purpose.