I have used low fees without many problems, sometimes to my surprise the transaction gets confirmed within a short period, some others I've had to wait days for them to confirm. On a couple of occasions after waiting forever, the tx were discarded by the network and the bitcoin returned to my wallet.
I always use default fee 0.0002 btc (can be said low fee). Because I usually use exchange sites for transactions (use c-cex). So the transaction and confirmation can be said faster. Maybe I should wait about 10-20 minutes to get confirmation?
Yeah, default fee at times seems to be low. This has never been a issue for me till date though lot of users complaint the delay in transaction confirmation a major issue. With me, I just place increased transaction fee during the time of gambling for faster confirmation whereas for normal transactions blockchain default fee suggested is paid.
Well the real problem is ratio between fee amount and transaction size in bytes since blocks are limited in size, 1MB. It's expressed in sat/B (satoshi per byte) end you can check which value you should target on
because it changes over time depending on current number of unconfirmed transactions.