No, you're absolutely right, if looks were a priority then I would've gone with 20"s on there. Truth is the old wheels were shot and needing refurbing completely, and they were ugly as sin too so I used this as an excuse to get something that looked better. The fact I've still dropped weight at each corner at the expense of the wheels sitting slightly further under at the rear means I've gained performance, and for me that was the most important thing.
I'd have loved to get a set of the M6 ones, but they are just ridiculous money and I'd have needed new tyres all round too.