yeah tis twice as much for 2 exhaustes so a normal powerflow is 200 so your def lookign at a good 400 quid and the size exit is a bit fancy so 500 will be a pretty fair bet.
Shop around a bit powerflow are far from the greatest.
i paid £360 for mine at powerflow for a quality stainless one on my old corsa, but prices and quality vary at powerflow retailers. Go to reputable one mate
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