At that sort of power I found that FTTs aren't up to it. I use them up to 30 ft lb and 31 grain Baracudas thereafter. The JSB Jumbos will be fine but I suspect they will cost you quite a bit more than Baracudas. Good luck anyway.
I hope the FTT's are ok but looks like they might be a turkey. The JSB Jumbos cost £12 for 350 which doesn't seem overly excessive.
You can spend thousands and still miss a barn door or spend just enough and enjoy yourself. If you haven't got the talent to start with a million pound won't fix it. Whippet, Russell, a few bang sticks and a flat cap. http://www.smart-tech1st.co.uk