Here's how it went - a very valuable reminder about "How the other EV half live"
From home we drove 240 miles to Flint, filled up and had a meal. Used Holyhead-charging as contingency. As it happened we had time and filled up to 95%.
GridServe Holyhead Clock Tower its a bit tricky to find, at the entrance to the ferry terminal take 1st exit off roundabout, past the railway station, and keep going (despite it looking daunting and commercial vehicles only). 3 stalls; GridServe website shows stall-occupancy;
There is a charger on the ferry (which I believe can be booked, but I don't want electricity from bunker-oil on my Eco-credentials)
Hotel in Dublin for a couple of days. The hotel had a charger (free). Did a couple of days touristing - day trips to National Stud and PowersCourt (which had Tesla chargers in the underground carpark at hotel whilst we walked around the garden and had lunch). Kids then came out to join us.
Headed off to Ennis. Stopped at Birdshill supercharger, and had a Subway at the services there. Plugshare showing that Ennis has a single 50kW charger - with one stall. Decided both of us queuing at the sole charger was pants and that we would sort that out at Galway. I lowered Plugshare filter to "any plug" and found that our hotel had a charger (the only hotel charger in Ennis). Wandered around that part of the car park on foot searching, expecting to get a tap on the shoulder from CCTV-watching security guard ... found it tucked into the corner of the carpark in an almost impossible to back into bay (car park was full, noone else had thought they could squeezer in). 3kW - Gosh! - but free. Took all night to charge up one car. Decided that we'd sort out the other car when we got to Galway.
Drove along the coast up the Wild Atlantic Way to Galway. Checked for anywhere for lunch with chargers - the only Tesla destination charger at Restaurant / Hotel PlugShare recent comment was "All 3 powered off and connectors covered in mud" so they lost our custom.
Phoned hotel in Galway "Do you have a car charger?" "No, but there is one just down the road". Indeed there was, at a petrol forecourt. Had a look on PlugShare - EasyGO. Comment said that Contactless wasn't working. Downloaded the EasyGO APP, it said "Can use credit card". Sounds OK. It was, indeed, only a short walk from the hotel. Tried M3 and MS, even with CHAdeMO adapter, nothing worked on Contactless. Tried the APP ... that charger was not showing on the map! and no QR code that I could find, also it was asking me to register (no actual mention of a credit card ability), and I have no access to email from my phone ... so that wasn't going to work. Beggars belief that these companies don't actually want my money. "EasyGO" my foot ...
Went to the nearest ESB (which I had downloaded the APP, registered, and got a RFID card for). Stall ["just the one" - there were about 5 x 50kW chargers in Galway all of them single-stall <sigh>] was occupied, wound down window "We'll only be 5 minutes"., Great! Plugged in, couldn't remember the password for the APP so that was out. Used RFID card without any trouble, charged the MS for 10 minutes and added 5%, then sat in the M3 for a hour while it charged. Added just enough so that we could get to Dublin - would charge at Holyhead, and queue, if necessary but if time would charge at Ionity half way to Dublin. A taxi turned up, parked along side us, didn't bother to ask how long we were going to be, then drove off after a couple of minutes. Then a Leaf did the same thing. No idea why ...
Whilst we were sat there we had a look at the feedback on Plugshare for Birdshill supercharger. Since 2017 there are only 2 x failed-to-charge reports, one an Outlander!! the other reported broken hardware but that user returned the following day and reported that it was working again.
The 50kW charger we used in Galway? In the past year 30% of the check-ins reported an error which prevented charging (and also that if the A/C was in use the charge from the DC was significantly reduced ...)
Got a message from ESB that it had topped up my account with £20 ... so I now need to figure out how to close my account and get the balance refunded <sigh>
Had a look on PlugShare for the return journey and discovered that Enfield Supercharger had opened, Thanks Elon! (closer to Dublin than Ionity, and I expect that the price at Ionity would be set to "eyewatering" for Teslas - that must be driving plenty of their business away too)
Had plenty of time so stopped at Enfield. (If you can be bothered you can stop at a "manual" toll, coming off, and get a receipt which will enable skipping the charge at subsequent toll, after re-joining, but that also requires using the manual toll. Not sure its worth it for a Euro or two. And you have to know to do that - there is a sign to that effect at the Supercharger ... bit late to get a receipt by then!). Had a coffee and a bun at the nearby posh hotel. Effortless like all Superchargers, charged to 100% so came off the ferry at Holyhead with 85%.
From Holyhead:
170 miles to Hilton park
Charged for 20 minutes
150 miles to home
Effortless.
Given we were doing convoy-trip a comparison is probably valid, and subjectively I would say the M3 LR had about 10% less range than the MS Raven