Used Halfords and never had an issue with the mots as they never reported anything wrong and I’ve used f1 for a air con recharge that cost only £12.50 (which someone kindly posted) again no issues. However I’ve had 2 tyres fitted by F1 which turned out were the wrong size which Halfords spotted when it went for the mot. But give them their due they swopped them after I contacted F1’s helpline so got 6 months free use out of them. I suppose it’s just the luck of the draw with any garage.
With my personal experience with F1 Oxford, I would not use them again even for free.
If I was currently driving I think I'd have to "splash the cash" and go with F1 !
Had issues with my local halfords autocentre, so would rather pay for f1 who have always been good for me.
Here it is; https://www.hotukdeals.com/deals/halfords-free-mot-with-any-halfords-retail-store-purchase-3043399