Also Purchased the CTEK MXS 5 as my car has hardly moved for 3 weeks, and when I did go to the supermarket in it the other day, even when warmed, noticed the S/S wouldn't cut in for the whole journey (there or back).
It arrived in 3 days from Amazon and had it on charge all day yesterday to get to stage 7. The engine just seems to turn over that bit quicker on the starter, and after nipping to the shops, noticed S/S was cutting back in after only 2 minutes driving (engine not even fully warmed).
Doing to do the wife's Polo over the weekend. Just peace of mind really.