Originally Posted by Nos4r2
Your flooding hull has been closed off. Do you still have the holes in the bow? If you do you need to block them too-and that small hole needs a screw in bung.
.....or get your holesaw out and reinstate the 4" hole at the transom!
I guess it depends what you want it for. The stability can be useful as Thomas says, but if you do a lot of stop - start then it can also be a pain in the bottom. Once the hull has emptied of the ballast water it behaves like any "sealed" hull. The only real difference is that it takes a bit longer to get up on the plane. Also with the ballast system it sits a bit lower at rest- good for rescue work (and I guess fishing?) as you're closer to the surface to pull people / tuna out. I had an SR4 with a 25 on the transom. Took about 20-30 seconds to drain & plane, but as it mostly was used for cruising it really wasn't a problem.
In short you either want a big hole at the back and the two small ones at the bow or none at all! Just remember that if you do reinstate the rear 4" hole to seal the perimiter properly or you'll get a floppy transom.