Jay de, yeah, does save labour costs. I'm an ex mechanic, so I'm not phased but this stuff, but I have to say that its really not a difficult task. Fiddilly, yes, but just nuts and bolts at the end of the day.
I don't have issues without a cat as I have the AGU engine with it early single lambda probe ecu, so it doesn't check for cat efficiency, therefore no check engine light.
I'd deffo do it again, I enjoy working on cars anyway. Fitted an number of things to friends cars for spare cash.
Very nice clean setup caney. I'm quite jealous from an engineering point of view. It looks sooo much easier to get at things on a top mount setup. BTW, love the 4 clamps on the boost pipe. You really don't want that coming off do you. I like the heat sheild for the coil pack loom. I've got some heat fabric left over, might give it a go.