I actually just made a kit with some sugar. I didnt add the sugar so much to get more alcohol but I find it helps fermentation along. I used 1 coopers can kit draft 3.75# prehopped LME - 3# LME and about and a little less then 2 cups of sugar. I know the fermentation went well - I just racked wo secondary and the gravity was down to 1013 - I didnt take an OG but im just gussing with those ammount of fermentables I would be up at about the 1050 mark.
I think if you use some sugar it should be fine - I have used it in the past - as long as you use it sparingly it's fine. All depends on your style of taste - if you want an award winning maybe not - personally I am pretty simple - I just like beer that is refreshing and tastes good - so it works for me