Well, the kicker is you state mostly fresh water. If it was ONLY fresh water, the Tiger would be a great choice. Great on gold and Tesoro warranty is top notch. BH is a good unit, but for me the older ones with the 9.5 inch coil are better...that 12 inch coil on the new ones is a bear to swing after a bit and for me, hard to control.
Once you hit that salt water, the higher end dual and multifrequency VLF units and most any PI unit would be a better choice. The PI's don't discriminate though, so its a battle when you get into iron infested areas.
There are several used CZ21's out there that the dealers have for sale...some pretty much like new. Only trouble is the warranty is probably up, but they are built very well.
Not sure what your budget is.