Floorstanders are typically:-
Fuller in sound, more obvious bass.
More impressive looking
Less likely to fall over (though still can)
Tidier looking, cables less visible
Standmounters do need stands, which can add 20% to 50% to the cost. They can sound more subtle and detailed. They are less likely to boom. Can seem less imposing in a smaller room.
The decision is very much a personal one, and both Neat and KEF have their advocates. KEF tend to be more measurment oriented; Neat are more listening oriented - but both are popular and well reviewed. Both will get significantly better with higher quality amplifiers and source material. So it depends what the rest of your friend's system is, as to how likely that you might get similar results yourself.
Your system as it is probably wouldn't benefit from £1500 speakers, but these might be a better long-term bet if you find some you like. Worth hearing other KEF R series and their LS50 models.