I had 50mm vs 65mm issues, I got around them by getting both (65mm second hand and in a bad way but very cheap, got it repaired) and the 50mm brand new at a stupidly low clearance price. I found that if on a 35mm system you really liked a 24mm lens, then go for the 50mm for a real wide effect. If you liked a 35mm lens on 35mm format, then go for the 65mm. Personally I use the 50mm and a 90mm as a good combination, the 65mm is a bit close to the 90, though if I was only taking one lens out, it would be the 65mm. Guess that doesn't help much does it?