need some help (uk/wales)

Well next month i am going on holiday with my dad and sister for a few days. It turns out we will be going somewhere in the mid-west of wales (not exactly canada as i requested but oh well) Apparently we will be within about 20 miles of the Machynlleth loop. Which is where the RAF do alot of high speed low level flying through the hills, a search on Anet will turn up photos of it. I am hoping to do a day of spotting to bring back some photos of the area, but i would like to know if anyone here has some experience with the area and could offer some good spotting locations and days/times, as i would like to bring back some good photos to share. If i can find this place on a busy day it would make up for missing various airshows.
Thanks guys.
Thanks guys.