Buying an unphotographed coin is always going to be pot luck. I would assume that such a coin has got defects if the price is lower than the going rate. If none of the coins photographed on a dealer's website are bargains, then I don't expect to find a bargain within the unphotographed ones either. BUNC could still have edge knocks, ugly contact marks, etc. I agree it is very annoying to buy a coin remotely only to realise that you would never have brought it in person. For that reason, I would rather miss out on a potential bargain than to risk getting annoyed afterwards.
I once brought a pair of slabbed MS62 coins from LCA unseen. I took a gamble because they added "with exceptional eye appeal" to the auction description. That turned out quite well.