I think the Day One and Flier are both lovely bikes and would likely be ideal for your needs. The only place I've seen a Smithfield is the aforementioned Cycle Heaven in York. They looked smart enough, but a very different kind of ride, I'd imagine. Cycle Heaven are very good about extended test rides if you fancied a day out.
Getting a bike hanger space has got to be a good thing, for keeping rust at bay as much as anything.
I fitted my own mudguards to my Day One and have no problem getting the back wheel out without faff - it's just a case of ensuring the stays are cut long enough to keep the guard far enough off the wheel to allow it to slide backwards several inches without touching the guard, which you'd hope the chaps and chapesses on the assembly line would be capable of....
My road bike came via C2W scheme so I can appreciate the appeal of the scheme, but if you are patient
ebay and the like throws up some real bargains. I got this for £250 last month - only 400 miles on the clock, Reynolds tubing as opposed to the unbranded steel on the newer models, SPD pedals included, Avid BB7 brakes, which are miles better than the frankly rather crap Promax on this year's Day One, and comes in at nearly 750g lighter than the new Day One. And, unlike with C2W, no need to fret that it actually belongs to someone else and that I'll still need to pay monthly for a bike I no longer have if the worst happens and it does get nicked -