I've just had, on a call-out, the RAC replace a 5 year Guaranteed Varta battery that was supplied and replaced by them in November 2020 ( on my 3.5 ltr Honda Legend ) on a Call-Out
They've replaced it with another 5yr Gteed Varta battery ...... but not extended the original warranty period tho' .... I hope this new battery lasts 5 years, but I doubt it !
On the other hand, I have had Yusua batteries for donkeys years on my Lexii and they have performed admirably ...... Toyota supplied apart from this last one on my ( new to me ) 91 Ls400 supplied by GSF ...... best price at £166 and 5 year warranty replacing the old Yusua one that had lasted some 8 years
Just hope for you that Halfords don't get their batteries from Varta !
Malc