I'm having a recurrence of, what I think is, a MAF sensor problem. I've tried cleaning it. Next plan is to replace. The LandRover sensor costs 3 times as much as the BritPart one, is it worth spending the extra?

Which engine? and do you know the LR part number for the sensor?

2.4 tdci. Paddocks give me these 2 options https://www.paddockspares.com/catalogsearch/result/?q=MHK501040

As your engine is a ford transit engine, it was (probably) originally fitted with genuine ford sensors. If you look at the numbers on the sensor, it will probably show FoMoCo and number 6C11 12B579 6335. This MAF item was fitted to a range of ford engined vehicles, including the transit vans. There are a few transit parts suppliers on eBay, I got a genuine one for under £30 and it works fine. Mine is slightly later than yours and has a similar but not identical MAF with a different part number, the seller has some with your part number but not showing as genuine however, bay item number 260964676335.
As it turned out my MAF was not the problem, it was doing its job and logging a fault, it was a split in the intercooler which I found later and sorted. Check your intercooler at the ends where the plastic inlet and outlet are joined to the core, it is a common failure point. And also check all the air hoes between the turbo and engine for splits and leaks. Let me know what you find, might be able to help with further info.

Cheers for reply. It's 6C11-12B579-AA. The problem I experience is power loss / limp mode when idling, or coming to a stop at a junction. Same thing happened earlier in the year, I cleaned the sensor then, but I was not convinced that this resolved the issue - the weather improved and that maybe resolved the problem. Now, the weather has suddenly become wintery again, and the problem returns ... I'll buy a replacement and see what happens, in the meantime we'll limp on.

If possible get a diagnostic tool on and see what fault codes are logged. This will help to home in on the problem. Also check the wires in the vicinity of the plug which connects to the Maf sensor, these sometimes fray or break.

Interestingly, while waiting for the new sensor to arrive, I was chatting to a pal who told me that most faults these days are battery related, because there are so many electrical components/sensors in modern engines and they need contact and sufficient power source. So I changed the battery and the problem seems to have gone away.

That is so true. I have extra items on mine which require a permanent live supply and it doesn't get used enough and so the battery tends to lose volts over time. I have got into the habit of checking battery voltage monthly and top up as required. I have found that all systems work fine as low as 12.2 volts for cold starting, but odd things happen below that. (first indication the battery is too low on volts is the alarm will sound when starting, and stop sounding as soon as the engine is running). However once you are started and moving, I would be surprised if all sensors weren't functioning correctly unless there is a charging problem.

Yeah I think maybe there was a charging problem, but it was a cheap and cheerful battery too - as you'd expect from the MOD.