The question is, on which port do people find a low-power unit? The block is more likely to be found on port 4334 or 3333. If you set it to port 4334, then there is a ball difficulty of 1,000,000. And with low power, which port is better?
what do you mean by "low-power"?
For high performance rigs and rentals its recommended to use 4334 since the minimum diff is 1,000,000
As for likelyhood of findng a block, there's no difference between either port the odds are based on the hashrate of your rig and that is all.