best new price for coils ive seen is £35 + vat each (same ones u need - short stubby type 1 bolt)
i've a similar prob where on occasion the car just bogs down in primary turbo mode.
it will hiccup in the high revs as well but very rarely.
im going to replace the maf, o2 sensor and coils in that order to try cure it.
maf this weekend and going to do full diagnostic as well will let ye know how i get on