Drove up 339 from Brandonville to Bloomsburg in October 2017 and found that now the whole length has been resurfaced. It's smooth and spectacular. Tight technical sections mixed with sweepers and all of it brand new. It's now one of the best roads I've seen in PA.
Northern section of 339 was resurfaced 2015-2016 and is great fun. Very smooth, high speed sweepers with the occasional tight twisty section.
BUT, the lower half of 339 (south of Buck Mountain Road) in 2016 was a bombed-out mess. Huge potholes everywhere, transverse ridges in the road over the drainage culverts. Scenery is beautiful but the road conditions make it very dangerous (on a sportbike anyway).
Fantastic scenery one of the nicest rides in the area and fun curves (not as many as 125 though). Tie this one and 125 and this one for a good loop. Its short but packs a punch.
Fantastic road with great views and many nice turns, well worth a look.