Premium vs Supreme Unleaded

[Pullock]

I know this is a long queried topic and I have scoured the internet for an answer but for one which involves my specific engine, which I haven't found any results for. So I have a 63 plate fiesta 1.6 Powershift Duratec Ti-VCT. I've been looking mainly into finding out if this engine has knock sensors to benefit from the higher octane but haven't found any answers. I've usually ran on 95 octane Premium Unleaded from my local Texaco station and if I was to try supreme (If it's worth it) would it be ok using the one at my local filling station or would it be better off going to Shell, BP etc. 

I know this was a fairly long post but any answers are appreciated and thanks for reading.

[m1tch]

To benefit for the better fuel you would need to remap the engine, on the OEM map just fill it good quality 95.

[Mitchell Rogers]

I seem to get a few mpg more with supreme and because it's really cheap atm anyway I will keep using it.

[Pullock]

I think I'll stick with Premium for the time being as the supreme is 8p per litre more than premium, but thanks for the replies.