Hi kurty!
It will always take a few hours to convert from one type to another. Whether it's high wing or low wing really doesn't make any difference to how long it takes to convert.
The things which you will notice are that your visibility of the ground will be obstructed in the low wing aircraft. You might have to think about this when navigating, in case the wing blocks your view of a navigation feature. And your passengers won't enjoy the view quite as much. On the flip side, in your Cessna, you'll be used to having your view obscured by the down-going wing as you turn. The view in a turn in a low-wing is much better, and you might find that the circuit is slightly easier because of this. But these differences are so minimal they're really barely worth mentioning, let alone worrying about.
On a more technical note, the fuel tanks will probably be below the engine, whereas you're used to them being above the engine. Depending on the type, you'll probably have at least two fuel pumps. If both of these should fail, you'll have an engine failure. On the PA28, the main pump is mechanical, and the backup pump is electrical, so the chances of failure are pretty remote. But if you were to have a total electrical failure, it's worth knowing that you don't have a backup fuel pump. Again, such a minor point that I'm not sure it's even worth mentioning.
As for floating in the flare, I think there are so many other things that affect this that any difference that the position of the wing might make would be so small as to be irrelevant.
What type are you thinking of renting?
Have fun!
FFF
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