I think I looked at that Wavepro 950 a couple of times as well but IIRC the price was slightly high for my taste
It was definitely a bit steep when first listed - even with the current dire state of the pound it would have been over 1100€ in the Netherlands, the auction didn't go that high fortunately
It's hard to know what stuff like this is worth - it doesn't look as though the 950 comes up all that much on ebay but for comparison there are a couple listed with BiN prices ranging from $1400 to $4500.
I think the top end of that is fantasy but a pair of DDA-260's (which are based on the 960) sold for $2200 each. They are a better 'scope as, apart from a 2GHz front end, they have the full 64M of acquisition memory so taking that into account $1400 for a 950 is not completely unreasonable.
This one could have been a bargain for someone though:
http://www.ebay.com/itm/LeCroy-WavePro-950-Oscilloscope-4-Ch-1-GHz-with-manuals-needs-repair-/272668492826.
The main reason I can think for channel 1 and 4 not working is that the 'scope has been set in 2 channel 8Gs/s mode
and I'm not sure whether it has enough processing power to do the math functions at reasonable speeds.
It seems common of the 'scopes of this era and, perhaps more so, of the 1990's that things were pushed a bit on processor power front. I suppose the argument is that it is better to have a slow FFT (or whatever) than no FFT.