Not better than, if you're going to do only one giving more results than doing one six week cycle at same weekly dosage. Not as good.
If the weekly dosage for a six week cycle is pretty substantial, then also probably a single 4 week cycle using the same total amount, and therefore a 50% higher dose per week, is not better. An exception may well be that if one is completely accustomed to doing say 750 mg/week total, then doing another 6 week cycle at 750 mg/week may do little extra whereas a shorter time at 1125 mg/week total (not that I've ever heard of anyone doing that odd number) might give a nice improvement.
Another exception could well be if the dose for the 6 week cycle is not so substantial, e.g. 500 mg/week total. A 4 week cycle at 750 mg/week might beat it for same total drug usage.
In terms of comparing equal total usage and equal number of weeks off per year, and comparing yearly results, my GUESS is that it would be pretty much a wash between the two protocols.