Good! You can use any cooler you want.
The Silver Arrow SB-E Extreme is £53.99 It comes with TY-143 2500rpm fans which add about 8c more cooling when ran at full speed of 2500rpm at 45dba. But if you keep it below 1300rpm it's the same noise level as normal SA SB-E at 25dba. Fans are PWM
http://www.overclockers.co.uk/showproduct.php?prodid=HS-099-TR&groupid=701&catid=2330&subcat=2352
Archon SB-E X2 £59.99 2x 140mm PWM fans. Single tower that cools as good as twin towers
http://www.overclockers.co.uk/showproduct.php?prodid=HS-106-TR&groupid=701&catid=2330&subcat=2352
Phanteks PH-TC14PE comes in white(silver cooler) £66.98 and other colors of red, blue, orange and black £69.98. not PWM fans but come with a PWM adapter
http://www.overclockers.co.uk/showproduct.php?prodid=HS-009-PT&groupid=701&catid=2330&subcat=2348
There's a white (silver) Phanteks TC14PE for £54.98 if your interested
http://www.overclockers.co.uk/showproduct.php?prodid=BG-006-PT&groupid=595&catid=678
Alpenfohn K2 £59.99 with 140mm and 120mm PWM fans
http://www.overclockers.co.uk/showproduct.php?prodid=HS-020-AL
Noctua NH-D14 £62.98 with 140 and 120mm non PWM fans
http://www.overclockers.co.uk/showproduct.php?prodid=HS-011-NC&groupid=701&catid=2330&subcat=2346
Normal Silver Arrow SB-E £57.98 PWM fans
http://www.overclockers.co.uk/showproduct.php?prodid=HS-078-TR&groupid=701&catid=2330&subcat=2352
Silver Arrow SB-E SE £59.99 PWM fans
http://www.overclockers.co.uk/showproduct.php?prodid=HS-101-TR&groupid=701&catid=2330&subcat=2352
BeQuiet! Dark Rock Pro 2 £61.99 135mm and 120mm PWM fans
http://www.overclockers.co.uk/showproduct.php?prodid=HS-005-BQ&groupid=701&catid=2330&subcat=2340
Black Megahalems £49.98 plus fans
http://www.overclockers.co.uk/showproduct.php?prodid=HS-019-PL&groupid=701&catid=2330&subcat=2349
and Blue Megahalems £48.19 plus fans
http://www.overclockers.co.uk/showproduct.php?prodid=HS-026-PL&groupid=701&catid=2330&subcat=2349
and Silver Megahalems £42.98 plus fans
http://www.overclockers.co.uk/showproduct.php?prodid=HS-005-PL&groupid=701&catid=2330&subcat=2349
I know it's a big list.. and these are only the best quickly off the top of my weak mind. I'm sure I've missed a few. Honestly most are all about the same cooling. It's more you liking one more than another.
Wow. Thanks for the list. Will go through it properly. My only issue is now how to fit it. I presume I can leave the 120mm fan on the back of the case and just remove cooler and radiator?