First quality shoes - advice needed

[corntote]

Hi there, I'm fairly new to shoes and need a bit of advice on my first decent pair. I'm in my early-mid twenties and work in a corporate environment. I need to look conservative, but also want to look my age. They will only be worn with a suit and need to be black.

After looking through the selection on Herring, I picked these as favourites:
Cheaney Lime - Looks great but is it a young enough look?
Cheaney Warwick - Current favourite. Note this is the top of my price range.
Loake Abberline - Poorer quality than the others but I like the last shape
Barker Blake

Which shoe?
Which of the above would you choose for my situation?

Which size?
Nowhere stocks Cheaneys in Sydney so I can't try them on. Are they typically bigger/smaller than other brands, or pretty standard?

Hopefully I can work my size out based my size in other shoes.
I'm a size 7 in all of the Church's shoes I've tried. I've also tried the Loake Gunny (which looks similar to the Cheaney Warwick) and seemed to be somewhere between a size 7 and 7.5 (the 7 felt a bit tight and the 7.5 looked noticeably big).

Thanks for any input!!