Apologies - tried a couple of searches

I haven't been back to the UK for a while and am heading over to the UK in November ex-Portland, Oregon. It seems UK credit cards have a 'chip' on them and a pin number to conduct a transaction. While in the UK, I'd like to use my BA Chase Visa (without a chip) - will this be readily accepted or cause any consternation in high street shops which accept Visa?

I also have a US Bank debit card too (with a pin) - would this be a better option? Just don't want to be 'embarrassed' at the check-out