Dollar store preg tests?

Jeralee • Married to the love of my life for 3 years. Ttc since March 2015. Hoping our BFP comes soon!! IVF #1- BFN
Do they work? I'm 9dpo and I've used FR and both bfn...probably too early to test but they are the cheap ones work? Anyone get a bfp with dollar store brand that was a true positive?