I can vouch for USfine. I have spent over $700 with them and never had a problem.
it depends if you want goldfarming or rapid gold to be honest. goldfarming is almost always late, and rapid gold is typically on time from my experience
Just buy from Sythe,there's alot of gold sellers here that easily match Usfines or Gold4rs prices some are ever cheaper.You'd get more for your money(my gold shop is cheap).
I can say i've had a successful order with both Sites,they never give you a correct time frame for completion.
If you are planning on buying rapid gold, buy it from neither - Purchase it from a trusted seller on Sythe, such as Hamjamk, King Tijn 2, or R2Pleasent.
Neither. I would highly suggest you buy from people here instead of one of those sites. They don't have the best feedback and can't speak very english very well.