I know Merlin do relatively cheap Deore groupset at £259 but is there anywhere cheaper than that. Actionsports.de seem to have very cheap ones at £210 ish, anybody had good experience with them? Anyone recommend anywhere else, would prefer to buy in the Uk but price is currently king at the minute.

Try Rosebikes and Hibike (both German)

I’ve used both and recently bought a replacement XT drive train from the latter at a significant saving over Merlin et al

I had an SLX group from actionsports.de last year, £203 which was cheaper than anywhere in the UK by quite a margin and it was with me in a couple of days. Would happily use them again.

Actionsports are great, fast despatch and a fast delivery service. Like rose bikes – 3 days from order to my desk.

Also worth a look are another couple of German retailers –
Bike Components and Bike24