Re: 302c rods
Longer rod and shorter piston = lower gudgeon pin angles which means less loading on bores and slower change of direction for the piston which means less chance of breaking gudgeon pins (anyone ever broken one?) and small ends on the rods. Also means that the piston spends slightly longer at TDC (and therefore BDC too) which in theory helps develop more torque although from what I gather it's only a small gain.
Basically if you are going to get new rods and pistons anyway and the compression that you'll end up with is suitable to your application, it's worth doing.
That's what I've been told although I've not run them myself before.
There are two types of fools.
The first, who thinks that because it is old, it is good
And the second, who thinks that because it is new, it is better.