If you are definitely going to avoid the SAM then why not use somewhere like the IW NDB or even an airways reporting point such as KATHY (right underneath the VFR recommended route). Just becasue you're not in the airway doesn't mean the point doesn't exist.
But to be clear: if you put SAM in and then don't call Solent, they will never miss your presence as they don't get the VFR FPL anyway.