I never had the chance to buy a 6800xt at a reasonable price, but I had a 5700 and 5700xt, awesome cards to mine, they gave me a good amount of ETH.
I bought before the peak for a good price, sold at the peak and had profits, my only regret is not buying 5 of each one 

Talking about AMD right now, it`s a good opportunity to gain market, since Nvidia are screwing with everything, prices are insane of RTX 4xxx. If AMD delivers performance with good prices, they can earn some unsatisfied customers from Nvidia.