Keep the connectors perfectly dry and they'll be fine. Wind blown rain and early morning condensation are double trouble.
I have been down the same path, and after many hours of research I have concluded that good quality cheap waterproof connectors don't exist. For some reason manufacturers charge 10-20x the price for simply adding a plastic shell with an O ring.
The only inexpensive connectors that I would consider barely acceptable are the 5 pin inline plug/socket combinations sold for use with LED garden lights.