I weight 280 lbs. and wife weighs 200 so obviously we're making our '08 400 work pretty hard on take-off. When we're underway it seems fine as 60mph is around 6000rpm. My question is, it seems that everyone uses 18 gm sliders for better performance. One member seemed to really like the 16 gm sliders he installed. I'm looking for much better take-off and if we can comfortably cruise at 65-70 mph that will be fine. Is there a reason why I should or shouldn't go with the 16 gm weights? Your knowledge and thoughts are much appreciated.