I have used TopCashBack recently for purchasing a VPN service at 60% discount, but for flights on expedia the cashback is only $2.50 and for packages today's deal is $50 max. I would rather buy BA flights directly from BA or AA.com and will forego the cashback, as I have seen the trouble few of my friends and family went through with Expedia and other travel sites, when they had to make changes or when they ran in to problems. At least for me, the cashback amount is not enough to take the risks but would do it if the cashback amount is attractive