The extra weight might make a hardly noticeable difference. The biggest difference you would notice is the extra hydralic flow of the tractor. The tractors get their stability from the hoe stabilizers (the same width/stability on any tractor model, because the hoe doesn't change from one tractor to another) and the FEL.
There would be a difference between the 47 and 48 hoe, because the stabilizers are different lengths.
On your other post about 4400 w/r-4's or 4600 r-1's, John made a good point of more mowing, get the 4400 or more hoe work, get the 4600. You'll get more manuverability out of the 4400, being a smaller machine. The r-4's would be more friendly to your turf, while the r-1's would give you a big traction advantage. If you're not slopping around in a lot of mud and you want to mow, r-4's would probably be a better choice.