The GPS and HR accuracy on 245 is way better than 235. Recently upgraded and very happy. It's so much better I'll upgrade again when a new one comes out. Didn't think it would make a difference so held off too long.
That's interesting to hear as I have read and seen in many reviews that the GPS is worse in the 245 as they moved to a different chipset (Sony I think?) which is better for battery life but worse for accuracy.