Thanks for all the input guys much appreciated.
I have ended up going for a pair of Reloop RP7000’s and the Traktor Z2. Chose the 7000’s over the 4000’s as it was only £80 extra and the Z2 was on such a good offer I couldn’t resist with the total package costing slightly over £800!
Now I need a new laptop as mine won’t run Traktor!?