Had some issues with starting , checked out twice by Skoda assist and Skoda dealer , system A1 with no apparent drain on battery, Dealer will have it back if problem persists , had to call Skoda assist twice recently and as I do leave car at airport parking in the winter I am going to buy a jump starter as a back up , CLARKS 900 gets good reviews ,I am not sure whether this model is big enough to start my 2.0 tdi 170hp, if any one has used this starter I would appreciate any feed back. Thanks

Can I change my question to have any of you guys ever used ANY reasonably priced jump  starter ,  did you find it performed satisfactorily . 

All I can offer is this:

 

http://www.autoexpress.co.uk/accessories-tyres/43148/clarke-jumpstart-900

 

Their reviews of cars aren't exactly great but it's a good start I guess!

 

Some manufacturers state the engine capacity that the booster can start.