@Laska2Meryls that sounds tough - so glad you sorted it in the end though. DS's Dad is supportive - they do have a great relationship. DS has a tendency to be a bit lazy at times and yes the xBOx drives me nuts too. I know at his Dads he won't get the chance to do much in the way of XBOX. His Dad has a farm (just a small holding, few sheep and things - not his main job) and runs a b&b from the farmhouse on weekends so I know there will be plenty of stuff for DS to do and to help out with. Also his Dad is very into cars and loves taking them apart and putting them back together - something they both love doing so plenty of 'project' opportunities for DS.
The thing is he obviously feels the grass is greener - perhaps he won't get nagged about revision etc but I think he'll be in for a surprise as my ex is quite a driven person who won't tolerate teenage attitude or laziness so maybe it's what he needs right now. My DH has always struggled with being disciplinarian with him as he frets about not being his 'real' dad. The step parent relationship is a complicated one!
Thanks for your kind words everyone - it doesn't seem real yet. I'm not looking forward to it but we are very very close and he's a really super lad so I know he won't drift away - my parents live near his Dad so a bother incentive for me to visit them more too!