The carrot can interfere with mine sometimes, I think it's pot luck on the combo of pointer and machine.
I don't think I'll get another garrott mine is about 7-10 years old so I've reckoned it's given me excellent service the only time it falsed was when someone gave me a Duracell battery on a dig, back to the car put a Vitara battery in no problem when I checked the two batteries the Duracell was about a millimetre smaller, it's now in my Laser Scout.
I know people who have had problems with new ones, makes me wonder if they are being made cheap someware, strange for a established manufacturer and when you look at Regtons site, the spare parts list puts me off. I will be getting a Deus later this year so don't want something that interfere, no doubt the XP pointer will be expensive, just wish they would get on with it, they said Spring 2016 now summer