They are I think both V2's just the Modular one don't have the 'V2' written. As far as I know the only difference between the two is only that the Modular one has like 4 cables that can be plugged out and in the Non Modular one there is no. I don't think it is worth the £10 increase to get modular. So I suggest the TX750 non M.
Thanks for your reply and information regard V2. I have £90.00 for budget and the TX750M would be better for me as I like case tidy and anything for good air flow. Thanks for your help I am going with the Modular.