It will make the beer less fermentable. This means it will be thicker. Literally. More density (which can be read on a hydrometer). So of course, it will have additional mouthfeel. As for being sweeter, well, there is more unfermentable sugars. Presumably those sugars could be tasted by a human tongue, wouldn't you think?
In Process: Mango Beer, Homebrewers Pale Ale
Bottled/Kegged:Spicy Light Rye, Rice-adjunct Pale Ale, Mild Bourbon Porter, Roasty Stout, Basic Light Mead, Bourbon County Stout Clone
Up Next: Berlinerweiss, Chocolate Raspberry Ale, and American IPA