So I'm now completely bitten by the DSLR bug, having had my D50 for 4 months: due in no small part to these forums (thanks folks

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Now that I can't bear to be without my camera, I've decided it's time to invest in a 50mm prime lens, so really looking for some advice from forum members or any experience you have using 50mm Nikon-mount primes. I'd certainly consider other makes (Sigma/Tamron) as well as Nikon, and probably initial budget £200-300 but willing to push it higher if it's going to make a difference as I want this lens to last for a bit so don't really want 'entry-level' quality.
Thanks in advance for any help you can give.
NB I'll probably be back in a few weeks for advice on telephoto lenses: I've got the 55-200mm AF-S Nikon G series as it was on a cheap deal, but not sure it performs especially well at the upper reaches so will probably look to upgrade, this was an impulse buy and a bit of a mistake with hindsight. But think I'll concentrate on getting a good prime first.