Just wondering if its ok for me to just plug my amiga into his tft monitor or would i need to mess around with the settings on my amiga?
It should work fine, but you may need to create an approprite screenmode if you don't already have one. TFT monitors work best at their native resolution (1024x768 for 15", 1280x1024 for 17" and 19" for example) and in my experience seem to like a 60Hz refresh rate (probably lower than you are using with your CRT).
It might be a good idea to set up a screenmode like this before you go, otherwise you may find you can't get a display and therefore can't change screenmode!
HTH
Robert