Yes i got one and loved it till i got the model above which does far more, i dont like the 7400 as it doesnt do stuff like intercepts solving quadratic equations, numerical differenciation/integraction, recurrence relations, circles, but i liked it, i used it for my GCSEs but now i'm doin P3 i like sumthing more advanced, it makes life really simple, i find shortcuts in almost all modules. Unfortunatly it cannot do algebra, though my dad has a calculatro which can I think its a Texas Ti 89, that is really cool it does loadsa algebra + 3d graphs and tons more but i cant afford £100 yet.
Also, you cant program your calculator for an exam, that is cheating.
Also have you used mathematica or MathCAD or Maple, they all do hugley complex mathematical things on computer, they are really fun, like if u happen to want to know what 300! is. lol, or maybe its just me whose sad.