I personally prefer lasix over aldoctone. Aldoctone is potassium sparring so I would recommend it simply because its more predictable to work with. A lot of guys mess up their peak with lasix. The difference between a few MG can mean a lot to your body. So one reason so many fail from it is dosage/duration. The fact that is not potassium sparring can be difficult for many to compensate by introducing a potassium load at any point. if you experiment with lasix and get this balancing act out it can be very usefull.
I know many see lasix as dated, but you still hear about guys like Jay Cutler even failing for it so it can be useful if experienced with it. I would recommend Aldoctone though overall to most.