[Closed] Hope Mono Mini vs Avid Juicy 3 - Rotor Sizes?

Hi, first post complete newb. Pretty sure some forum Nazi at some stage will come shoot me down!

Anyway, I used to own some juicy 3's from new they worked great locked out when needed were fine (160mm rotors front and back). Recently got a new bike which had some Hope mono mini's with 160mm rotors front and back and due to Hope's reputation I presumed these were gunna be the bee's knee's. This just isnt the case,they rarely lock out even when really squeezeing the brake lever (when they do lock it seems to be when its wet), but not always. I took them to my local shop who bled them and cleaned them properly for me but they are still the same.
So I was just wondering what peoples thoughts on this were?
I was also looking at maybe changeing my rotor size. I was thinking putting a 180mm rotor on the back as thats the one i prefer to lock when rideing. Any advice on what adapter I would need for a Specialized rockhopper to fit this rotor with a mono mini? Anyone selling the adapter and rotor on the cheap?

Thanks for reading hopefully someone with a bit more know how can enlighten me?

Mat