Been using a Snipe ( not the full pro version) for the past couple of years without problem, does exactly what it is described as being able to do. I didn't get it fixed permanently to the caravan roof, just pop it up on to the roof through one of the Heiki roof windows. As Woodentop said you still need a clear line of sight to the satellite and a dish, tripod and length of cable might be better in some circumstances. I find though that having it on the roof does give a bit of a height advantage if there happens to large hedges about for example and with it not being a permanent fixture I do have a bit of leeway as far as moving it about on the roof goes. It weighs about 10 kg, is small and squat so never had a problem with it moving about in strong winds, I do put a square of rubber mat between it and the roof just to ensure no scratches on the roof. If you were planning on using it abroad you might find it loses the signal from about the middle of France southwards. It does pick up Sky channels 60 miles south of Tours, I do know that from personal experience. Can't give you any comparison with the other system you mentioned, never used it.
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