There are some voices with built in slide, but I have never thought they were very realistic because the length or depth of the slide cannot be tailored and the way you activate them - sharp press of the key - changes the volume. Don Mason is an expert at using the pitch bend wheel, and has mastered moving his lh from the chord to add the pitch change and back without missing a chord change. He is the best I have heard using this method, and it always sounds very authentic. I prefer to use an expression pedal to bend and slide notes. It seems the easy way to make note slide sound very realistic, not just on guitar, but on sax and trombone. I played piano, drums and guitar, so using foot pedals was normal for me but with a little practice I think anyone can master this.
Mike