
Matt...
The Irfon is a lovely river and late september should be a spanking time to fish it. You say in another thread that you are a bit of a river virgin so here's my advice for what it's worth, though there are others on here who can offer better

If you are looking for a guide who knows the system, Sage on this forum should know a thing or two
Firstly the beats:
I am presuming that you are fishing one of the WUF beats but have yet to decide which? I would head for one of the following:
Cefnllysgwynne, Gofynne or The Cammarch Hotel stretch. All are fishable with a 8ft 6 or 9ft 5wt. You could go smaller and lighter but I would not recommend going bigger. The wading on the Irfon is not easy in places and I would not go without chesties, and stud/felt mixed soles, this is particularly the case at Cefn. Cefn and Gofynne are lower beats and the water is quite big there. All the beats contain a good head of grayling and trout - some of them very large indeed!
I would give Seth at the foundation a ring and pick his brains, he is very helpful indeed and will be able to point you towards water of the best condition.
In terms of flies, dries: take some griffiths gnats and some Adams, balck klinks are good too. Nymphs: gold head GRHE and PTNs will do very nicely. Excellent local knowledge and some good local patterns can be obtained from Bill Price at Rods 'N' Reels is Builth Wells - he stocks a great locally tied pattern called a Cows 4rse!
WHether you catch or not, you will have a lovely day out, the Irfon Valley is just stunning.
Tight Lines
Dave
PS drop me a PM if I can be of any more help
__________________
"A homeward tramp thro' mist wrapped night,
With heart and creel in common light,
Complete content, the day has brought it,
They fished for pleasure - and they caught it"
P F Morgan
taken from the catch record book at Llanthony Hotel, Honddu Valley, Aug 1942
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