Buying and installing a Snipe system

Surfer

Has any one bought the Snipe satellite system and if so does it function okay especially if travelling overseas ie southern France or Spain?  What model do you have as there appear to be several different models?

Also does it have to be screwed into the roof or will a decent sealant like Sikaflex work okay.  Not too keen on screws into the roof in case the unit needs to be moved to another caravan at some point in the future.  Thanks.