Apologies for the poor image from my all-expenses paid camping trip to Dungeness. Living the dream. I’d just cycled 90 minutes into the wind on a MTB. AND I’d forgotten my cycling shorts and was wearing running shorts and some long lycra swim shorts (seriously). Half way there!
I can confirm that the Spartan ULTRA works in high radiation areas, also making it a bit easier to find in the evening due to the afterglow. As you can see from the image I can also confirm it doesn’t work with an ANT+ HRM…sigh.
If someone could tell me why there is a lighthouse at Dungeness (nuclear power station in SE England) I’d be interested. Well. A little bit interested. 
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Did you mean why they built a power station next to an old lighthouse?
The lighthouse was there to stop sailors from hitting the headland. Less relevant these days, especially since the advent of low energy bulbs in lighthouses (not joking, I nearly ran aground in Ireland as a result!). GPS has largely replaced this function but the lighthouses look nice to most and can be useful if electronics fail.
The power station would have been put somewhere with as few NIMBYs as possible. Lighthouses, headlands, Scotland are all excellent for this purpose. Since the lighthouse is automated, there is nobody to complain when you build a powerstation next door.
I still want to know which is more readable in sunlight/indoors/clouds between Fenix and Spartan. The Fenix screen is excellent outdoors as it should be. I struggle with it in the pool I think due to the font so use a 920XT there. The Spartan appears a similar screen to Apple and other smart devices which I find appalling outdoors but better inside. I’ve yet to see a Spartan, and certainly won’t be spending my money until Garmin and Polar play their current hands!
Spartan is broadly ok. it always seem to be in display-off mode when I look at it when swimming. i’m working up the energy to review it properly soon. hence the visit to the nuclear power station.
Cycling in swim shorts…. you’re such a badass!
PITA maybe.