Best SIM only plan at the moment?

Like any other mobile provider it depends on your location, signal strength, coverage, proximity to a mast, etc. Other factors include the building you're in - at home I have incredibly bad performance indoors, but as soon as i step outside it just shoots up, and that happens with all providers and is entirely on the building. It doesn't seem that's the case for you though.

GoMo use a different network (Eir) to Clear (Vodafone). You may be in a coverage blackspot for them. You may also get completely different results again on the Three network.

You should be able to go back to Clear via the standard provider switching method, but you may still be liable for the first month of GoMo, unless the statutory cooling-down period applies; I don't know if so.

I don't see why you'd need to re-register unless Clear have somehow messed-up their processes. The standard provider change method - order a SIM, provide your details, select the option to keep your old number, wait for the SIM to arrive, swap it out, wait a short while for the changeover to happen - should be no different.

The only thing to watch out for is that if you took an eSIM from GoMo you'll need to delete it first via your phone settings before popping in the new SIM.

My home broadband is on the blink in a very weird way. Some things are working but strangely I can't stream music, internet radio etc. I've an engineer callout scheduled for next week but was thinking of getting a SIM to put in a spare phone to use as a hotspot in the meantime.

Currently using Clear and very impressed - could I get a second sim from them and cancel pretty much immediately so I only pay for a month?

Or which would be the quickest way to get 5G up and running quickly and not involve a contract?

Thanks. I might just grab a SIM from Vodafone as I know the coverage is really good in the house and there's a shop near me. Hopefully it's only for a week but I'll have a look at routers as a backup.

Who's got the cheapest SIM?
Doesnt need data, just receiving SMS really.
Doesnt need to last a whole month….

None of the plans let you keep the plan fee as credit, so you might want to stay put but if you want to switch here are some options -

Clear Mobile (Vodafone) - €12.99pm, unlimited 5G data, unlimited mins & 10k texts, 23GB EU roaming data, Bill-pay (€30 out of plan cap)

GoMo (eir) - €14.99pm, unlimited 5G data, 45k mins & 10k texts, 23GB EU roaming data, Bill-pay (€30 out of plan cap)

48 (Three) - €9.99pm for 6m (€12.99pm thereafter), unlimited 5G data, 5k mins & 5k texts, 20GB EU roaming data, no WiFi Calling or VoLTE so no mobile data when on call, Prepay

Tesco (Three) - €15pm with Clubcard, unlimited 5G data, 1k mins & 1k texts, 29.56GB EU roaming data, 100 International mins, no WiFi Calling or VoLTE, Prepay

No interest in porting as I want to stay on the VF network as I know it's very good indoors which is where I need it for the next week.

Picked up a VF sim this morning and topped up so I've got that running off a spare phone. Strangely, they didn't even ask my name, never mind look for ID etc.

Sorry, my post wasn't clear - I was referring to terminating a one month contract without notice, if you were to get a 2nd Clear Mobile sim.