I have bigger and better Weller stations, but when I tested a friend's WHS-40 I was disappointed. The power is too low, so the tip temperature cannot be well controlled.
I think that maybe others were disappointed too, because most pro dealers do not stock it anymore.
For a lower price you can get a good Chinese Hakko clone, or one of the Zhongdi made, OEM labeled, units (they are not bad, and cost half the price of a WHS-40).
A better Weller unit will maybe be too expensive for you, but for about the same price of the WHS40 you can buy an HAKKO FX-888D.
I don't know the price in UK (I've seen a thread in the forum), but you can get it from Batterfly in Italy for 98.00 Euros, and if you search the forum you'll find that they offer a discount for EEVblog members
http://www.batterfly.com/shop/hakko_fx-888dBest regards