No. Just no. They all use the same cable from your house to the exchange, in terms of core network, hardware, billing, complaints and CS they can be very, very different.
Now is Sky's budget brand, same way BT own Plusnet. Sky use what you will often find incorrectly called MER, or MAC Encapsulated Routing, it's actually DHCP Option 60/61 but this misnomer has persisted, it can make using 3rd party routers more difficult, but it doesn't require you to extract any info at this stage, if someone tells you otherwise, they are mistaken. Plusnet is UK based, they don't have overly scripted CS/faults and are generally easy to deal with, similar with Sky/Now. If something goes wrong, BT can be a PITA to deal with, I mean you can literally tell them the issue, tell them what process they need to follow and what they need to do and get nowhere. They are able to order upskilled techs on faults though, Sky/Now used to go 'cheap' as default, they also tend to use a different connectivity approach to bring you back to core. If BT mess up, they are more inclined to throw money at you, but anyone who has opted into the OFCOM compensation scheme should play by the same rules now, I made a profit from being a BT customer for over two years, but it wasn't a fun few months and someone at the CEO complaints team had to have a disciplinary as a result, I can't imagine the issue would have existed with anyone else other than BT and took a well known industry media outlet leaning on them to get them to acknowledge the mistake. Vodafone are just a bad idea for FTTC, CS/complaints/billing, policies are all questionable, but they have U turned on the policy side and seem to be reducing the rest, but the hardware isn't great either.
If it were me, Plusnet or Sky/Now would be my choice, but I value easy to deal with over saving £2, but check Quidco/TCB and consider that BF is later this month, so we should have a decent selection of promotion going on now, Sky are likely to offer a decent cash back deal on TV/phone/broadband if you're taking a TV service.