looking at a lot of the branded ones, the actual plastic body is in many cases identical so i suspect they are made in some factgory and just badged accordingly. that said i have a kewtech one, 50m and does alright.
If you have the time and patience, get yourself a cable reel and make your own
Outdoor Revolution Cable Tidy Reel - For 25M Lead: Amazon.co.uk: Car & Motorbike
www.amazon.co.uk
then some cable and get the adaptors for the cable at each end off flea bay and you are good to go. will have change out of £40 i reckon.