A bit of a niche item; only worth it for fairly involved weekend mechanics!
This is usually between £50 and £100 depending on where you buy. Around £50 in Amazon. It has been cheaper (£20?).
It gets really good reviews compared with other electric wrenches owing to variable speed.
Far better and quieter option than a cheap compressor and cheap air tools.
For OCCASIONAL use by home mechanics (like me) on stuck nuts, wheel lugs, suspension parts etc, you can't go wrong IMO.