Hi Niall,
We won't be going that far north. We'll be coming in from Stanhope - Consett - Whickham. Happy to meet for a coffee at any of those places.
The Q45 is very happy on the UK roads. The original 650 wheels have 42mm tires which can take on any reasonable gravel routes like disused railways and canal paths.
I've just changed these to significantly faster 700 gravel wheels with 35mm tubeless tires. They are still happy with potholes, much happier than the standard road bikes that's for sure
The standard Microshift derailleur is ok-ish and with the standard chainring/cassette gives you a lowest gear of 42/42 so 1/1 which can take on most reasonable hills. However for the C2C I decided that I wanted more range so I changed into a 12-speed SRAM 10-50 cassette and SRAM GX Eagle derailleur. Shifting is a significant improvement and of course more range at either end.
Re your points, very valid:
1. I've not tried clipless yet, starting off might actually be easier with clipless as you clip in one shoe and can do full turns with a single leg, then once going, clip the other leg in (see some of the videos of the Florida gettogether). I've not done clipless as I want to do the C2C with normal shoes.
2. Looking over your shoulder is indeed different so if the t-junction isn't a straight angle but say 45 degrees coming from the right (the driving side here in the UK), it is difficult to see so in those cases I stop properly and look before joining the road. Also, on DF bikes I've never considered a rearview mirror, but on the CB I have one and use it a lot.
3. Neck pain - absolutely none whatso-ever. I have my seat quite far reclined so probably similar to the S40 and my neck is in a normal position as opposed to the stretching back position you would have on a DF.
4. The Q45 has rear suspension
Super comfortable.
5. Here in Yorkshire we have some short very steep climbs (15 - 20%) which I happily do on the Q45, especially with the new gearing that I put on. On one of those very steep short climbs I posted my second fastest time. My fastest time was when I was 10 years younger
Also longer climbs are not an issue. I am still slower on those than with my DF but they are totally rideable.
6. Wheel slip, only had that once when on a steep bit of gravel path, a bank to get up to a railway path. Still despite the wheelslip I managed to get up the bank without having to get off.
7. Shins don't get anywhere near the bar on the Q45. Your upper legs might, but then you can just adjust the bar closer to you. I can't imagine this being any different with the S40.
I was seriously debating between the Q45 and the S40 and I'm sure I would have been just as happy with an S40, it's just that I found a nearly new Q45 with the right spec (thru-axels) and numerous accessories here in the UK for a reasonable price. If I'd found a S40 in the same situation, I probably would have ended up with that one.
Hope that helps,
Ted