Go for the full lower farings, I did.
Just fitted them on Friday afternoon and they look great!
I spent ages looking for a set on ebay and settled on a pair that needed a little filler on some scratches and respraying anyway from blue to silver. The plastics cost £40, filler etc £20 (by me) and spraying £not sure yet as I havn't had the bill but the total will not be anywhere near the cost of a new set.
Tedious but worth the effort