ie. a £4 X-lite one is the same as a £6 USE one, correct-o-mundo?

Not sure ,I think the X-lite ones are all alloy whereas the USE ones are thermoplastic except for the really thin ones (i.e. 26.8 upt 27.2)

i use a plastic USE one in my P7 as I spent 3 half days carefully hacksawing the old alloy post out after it bonded to the inside of the seatube.

unfortunately the USE plastic one doesn't come in the 28.6mm – 27.2mm sizing I need 🙁 so either one will be alloy?

In that case buy the X-lite one and a bag of chips with the £2 saving 😀 .

mmmmmm….. chiiiipsss 🙂