Hi Mate, going back about 10 years ago I had a Randle 26 with a Mercruiser sterndrive. The motor was getting to the end of its life and I was sick of spending money on it. Plus being a moored boat the constant growth and maintenance on the sterndrive was a real pain in the neck. After a lot of debating I bit the bullet and had a pod made up by GKS Fibreglass in Wangara, from memory it was about $2,500 for the pod. I wanted it to look factory built with built in marlin board. I also had the rear deck glassed up to replace the raised engine hatch as well as flybridge dash glassed up from the old gages.  I then purchased a 250hp Yamaha. It was a lot more reliable and a lot less hassle than the sterndrive but I would have to say I wouldn’t do it again. The boat never handled quite the same. I think having the heavy Mercruiser engine down low in the hull certainly assisted with stability. I still see the old boat around from time to time and it is still going strong by the looks of it. I think twin engines may have made a difference but I didn’t want to spend the extra cash at the time. If I had my time over again I would have dropped another Mercruiser in it, a lot less hassle and the boat would have handled a lot better.

 performance of the boat would be affected. I just don't like the stern drives, and there are very few decent boats around for sale that have a shaft & keel, which is what i would ultimately prefer.  cheers

 Most people shy away from shaft drives because they are afraid of no being able to handle the boat when in fact it is easier to steer and park than an outboard or stern drive boat.

Lot less maintenance and though a bit slower than the others , more comfortable ride and more reliable

 I always wanted to upgrade to a Fury 32. Diesel, shaft drive with full keel. They come up ocassionaly at reasonably good value for money. 

 I know it's a big bigger than the boats you have mentioned but have you looked at the 35 bertie with twin Suzuki's for sale at the moment? Be a great rotto boat. 

I nearly did this on a 26 Carribean about 12 months ago.

Price for a good pod was about 5k installed.

You also need to factor in some costs for fibreglass work on the transom before the pod goes on too 

Unless you’re a Naval Architect or engage one to carry out all the necessary calculations for correct size weight volume power effect on stability draft etc then you’re rolling the dice