This card is amazing when combined with other cards. Since it is a Sceptile, it is almost a destiny that it be paired with its brother, Sceptile GE. When combined, each of the AR Sceptile's Grass energies are doubled allowing Sceptile AR to strike the opponent for 40 damage per grass energy card. 120 damage for 3 energy is just awesome (but only 60 w/o the energy boost).
It heals itself with each grass energy card attached as well, so add something like Dawn Stadium and three damage counters are removed instead; this is a fourth of AR Sceptile's HP restored for each grass energy attached! Nidoqueen RR and Tangrowth Lv. X are possible techs towards this card's healing benefits. Expert Belt + Shaymin Lv. X adds 60 HP and 20 damage. I built a deck around this concept and won second in my local Cities.
The only bad things I see about the card is the second attack is often overshadowed in preference for its first attack, retreat cost is 2 (1 w/ Sceptile GE), and HP is low compared to most Stage 2 pokemon. Weakness really hurts with the current meta, but at least there are ways to deal with it (Metapod HGSS, Exploud SV, Bubble Coat).
Modified: 8/10
(an absolute must though in a 'DP-on format' Sceptile deck)
Limited: 6/10 (Tangrowth Lv. X is from the same set.)