the thall has a flex patter of 5 in the tips 8 underfoot and 5.5 in the tails. This makes the ski ideal for jibs and rails and medium jumps, soft tips and tails make them more buttery. The ar7 has a flex pattern of 6 in the tips 8 underfoot and 7 in the tails. This helps the ski be more stable in large jumps, not as buttery as the thalls. it can handle the all-mountain better than the thall since it is stiffer. Both have the ar50 sidewall construction(blend of cap construction and abs making the ski have a lower swing weight but stable, and durable underfoot), both also have the s7 base. If you do large jumps and a lot of rails, with some all-mountain pick the ar7, if you do medium to small jumps and a lot of jibs and rails and shit, pick the thall.