Ash, you can't go wrong with a set of HIDs mate. Forget all the claims on brighter bulbs and better night vision no halogen bulb is really that great. The blue ones and coated bulbs are even worse, the coating takes away it's full brightness.
Get yourself a set if HIDs from somewhere like HIDS4U, don't use eBay as the kits can be poor quality and the beam pattern very poor, not to mention the colour. Easy to think eBay against the pricier online stores but trust me, I've tried a few.
I got mine from HIDs4U, the ones with the beam block that helps light scatter. Even though the IS has an offset bulb it still makes a difference. I have 5000k, the best likeness and colour temp in relation to OEM 4000k. Anything more look too blue in my opinion and again you begin to loose the benefit and purpose.
Buy from here http://www.hids4u.co.uk/?gclid=CIeSktzszL0CFekBwwod71sANA and you'll wonder how you managed without them. When I drive a car with halogen bulbs now it's like having candles in the headlights!