Farnborough are always friendly and helpful, and like Irv says, as long as you keep clear of the Odiham ATZ, it's usually a case of anything goes. Lasham is generally more of a problem than Odiham, Farnborough will tell you if they're active.
As for call sign, I use Farnborough Radar if I want a LARS service from them, or Farnborough Zone if I want to transit the MATZ, but I don't think it really matters.
As for phoned Southampton, I've never done this, but I have phoned other ATC units for flight planning advice, and they are always, without exception, helpful. They'd much rather you phone before your flight than take off without having planned properly!
FFF
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