Agree with what everyone has said.
Nothing wrong with any of the plastic kegs, but the way to go is cornies. I've just ordered my next 2 from Norm.
I currently have 7 plastic kegs of various different types, both with Top Taps and Bottom Taps and to be honest couldn't say that any one is better than another really, they all have their plus points and down points.
I actually find the budget kegs to be most reliable, the caps seal easier and the lever taps they have are better than Drum Taps.
If I was buying a plastic Keg now then I would just get a cheapo budget one, I don't think the expensive ones are any better.
If I was looking for a longer term investment I'd be getting cornies.
Norm is currently selling his budget cornies 2 for £70, they are a bit bashed but they work just fine. then all you need is a tap, a CO2 bottle and a regulator and some beer, and off you go.