Rowly - You will get many positive responses about hybrid bgill so for your reference, I will supply a few of the negatives about hybrid bgill; Cecil B.1 also is well aware of many of the negatives of hybrid bgill and maybe 'we' can coax a few additional comments of hyb bgill out of him.
NOTE: Some of these negatives and maybe most of them can, by some, be considered POSITIVES; depends on point of view and which side you're arguing.
1. They are very aggressive, very easy to catch and fish out of your pond. Poachers can clean you out of prize fish very quickly.
2. Aggressive nature leads them to bite swimmers with no hesitation. Larger hybrids have rasping teeth around the mouth and have been reported to draw blood from moles, nipples & scabs; fish think these dark spots are snails. Swimming grandkids & women hate hybrid bgill when they get bit while swimming; an suprise and hurt!
3. Depending on the cross (parentage) 60 to 90% are males. Number of young produced is very limited and by themselves to produce forage for bass; the bass usually will not grow any bigger than 13" due to low amount of food. Successive generations may be more prolific and produce more young but ---
4. The offspring (F2, F3, F4 generation), I'm told by numerous fish hatchers, is trash, since in many cases they will not grow any larger than 4-6 depending on the generation". Ken Holyoak producer of the Georgia Giant bream says "F-2's aren't quite as good as F1 generation ". I have never tried to raise any of the F2 or F3 generation offspring in a cage or in an isolated pond to verify this fact. In a pond with mixed species or generations it would be very difficult to acurately visually determine which generation you were seeing. Reproduction may occur more than once a summer which commonly happens with sunfishes.

5. The gene pool of the offspring, with each generation, progressively reverts back to the dominate parent which in many cases is a green sunfish. I shouldn't have to tell anyone about the negatives of green sunfish. A quote about his hybrid bream from Ken Holyoak of Ken's Fish Farm, "Over a period of time, with inbreeding fish become smaller". "This a reason it is necesary to drain or poison out and restock your pond every few years". Holyoak claims this is true for all bream but I have found it primarily applies to ponds that are dominated with any form of hybrid bgill. North of the Ohio River, we have many ponds that are 30-40 years old and still producing large bgill with good growth of the pure northern strain.

6. Knowing the above two comments, the gene pool of the sunfish in a pond of reproducing hybrids would be a "mixed up mess" after several years. These fish, I would personally call "genetic trash".
7. Restocking hybrid bgill with adult bass in the pond will require you to restock large uneatable fish by the bass if you expect any number of teh stocking to survive. Quote K. Holyoak of Georgia Giant fame: "We do not recommend stocking baby fish in a pond already stocked with big fish". "Small ones should be grown in cages or small ponds until they are large enough to be safely stocked with big fish". Or large hybrids can be purchased for direct restocking.
8. When you fish them out of your pond (3-5yrs), it is recommended you completely clean it out and start over with the new batch. This will insure you get rid of any & all of the "trash" undersided offspring that may have survived.
9.. Zett's Fish Hatchery Drifting PA tried them & quit selling them due to all the negatives about them. See their testimony in their catalog.

ANY Comments from others with good reliable experiences?

aka Pond Doctor & Dr. Perca Read Pond Boss Magazine -
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