Murdock, since I'm not too familiar with fresh water diving my last post was intended to be a roundup of facts with no recommendation. However, you, like many, seem to be asking "what do you think?". That's fair enough and a challenge to give a non wussy answer.
Since I'm not in a position to say what I "like", I went to the court of last resort, arithmetic. It's well known that fresh water weighs about 3% less than sea water. Therefore, as an example, a well trimmed diver weighing, say, 240 pounds with all his equipments would displace about 7 pounds less than a comparable diver in seawater.
Now, I gotcha'--- because it's easy to imagine the feeling of being 7 pounds less buoyant. With this in mind I would recommend you seriously consider the relatively inexpensive aluminum tank. It's buoyancy in freshwater, empty, would still be 3 pounds, but so what? It's freshwater buoyancy, when full, would be negative three pounds or thereabout. Add in the weight of the valve and bits of hardware like D rings, knife and buckles and, even with a wetsuit, you aren't looking at an overly buoyant kit. A few pounds of lead should do the trick and it should actually amount to about 7 pounds less than a comparable "salty" would use. Voila, objection gone.
It's the buoyancy of the aluminum tank which turns off some divers. However, After looking at Rodale's data for LP steel tanks, and in view of the above calculations, it seems that any differences of feel and usefulness of the two types should not be decisive in freshwater. In any event it should not be worth the extra cost of steel.
I recommend you give first consideration to a new aluminum tank. These are widely available at discount prices. However, should you intend to make a rather big technical and financial leap to drysuit diving, I think you would find the PST LP tank attractive.