Hi Adam, I've flown over or close to Stapleford many times and do usually transfer to Stapleford Radio - particularly if Farnborough suggest it, as they may have noticed radar traces in the area with no altitude readouts. On a "Basic Service", Stapleford will generally confirm their QNH, runway in use and any known circuit, joining or over-flying traffic. I have never found them anything but helpful and indeed grateful for your call when you transfer back to Farnborough, as you're helping them maintain awareness of what you're up to. As others have said, it's good airmanship to keep others aware of your whereabouts and intentions and since the local traffic will probably be on 122.8 and not a Farnborough frequency, you get the information first-hand and can visualise any potential conflicts. In practice I fly at 2300ft, 2-3nm to the south of Stapleford (using DME from the LAM VOR), which avoids any of the North Weald / 1500ft stuff mentioned elsewhere, keeps you just north of the London City control area, and is also outside the 2nm radius of Stapleford's ATZ as well as being above it.