Sim900 vs Sim800 modules ?

Hi,

Have used a Sim900 module to output SMS alarm messages from my micro projects and it works well.

The Sim800 modules seem to have taken over from the 900, but wonder how reliable they are ?
Reading from these and other pages seems they suffer from various problems , but not sure if thats more to do with the country they are being used in etc.

Anyone here in the UK have any longer term experience of these Sim800 modules ?

( know in many countries 2G is being turned off, which both these Sim modules use, but from what I have read the UK might be hanging on to it for longer, even letting 3G go before 2G)

As far as I'm aware there's no more problems with SIM800 than SIM900, if they are 'taking over' in any way, it's simply due to their small size and low cost - I'm certainly using SIM800's in preference to 900's for both those reasons. In either case, most problems are due to PSU deficiencies, the high current spikes cause all kinds of problems if you don't take sufficient precautions - obvious ones are reseting of the module or processor.

As far as 2G goes, there are VAST numbers of 2G based systems out there, and for most purposes there's no advantage moving to 3G, 4G or 5G - small amounts of data via GSM or GPRS are better done using 2G, particularly as much of the equipment out there is in seriously rural areas, where 2G is likely to be by far the best coverage.

I know that EE are growing their 2G and 4G networks, 3G will be switched off in the future.
2G in the UK is huge, a large portion on the NHS's network operates on 2G and EE hold the biggest contract. Not only that but 2G is perfect for IOT devices.