Nah havnt used it myself man, I buy all my stuff in "bricks and mortar" shops, means if something doesnt work you just bring it back and they give you a new one straight away. Most places will give you discounts if they see you buying stuff a few times.
www.bloomandgrow.ie do a 10% discount for Rollitup.org members, use discount code ROLLITUP420 in the "voucher" section to get 10% off total price, they're not that expensive either and Iv returned a ballast after a year and it was swapped no questions asked.
But let us know how you get on with the other crowd, be good to get more of a variety of products!