Tbh polling in recent years has got far more difficult as the voter base has got far more diverse so the same strategies that worked for an older/whiter pool no longer do.
NYT Sienna is generally very good and I love their vopen data but they have had their face-plants too.
Personally I rely on the average of all of them and remember that a) the trend is your friend until it isn’t b) there is always a margin of error even in the best conducted poll.
Our polling averages track the latest trends in the presidential race, using data from national and battleground state polls.
www.nytimes.com
Edit I used to rely on RCP for my averages but in recent years they seem to have tried to put their thumb on the scale by including some very dodgy polls at equal weight.