Trick Titanium, Pankyl & Arrow to name a few, what motor, application & budget?

The heavier the rod the stronger the rod, but does weight concern you? If its a race motor and getting stripped frequently and you have a ton of money as you normally throw them at intervals then aluminium rods might suit, there are heaps of people who make them, but only a certain few make good ones.

Maybe consult your engine builder?