I have used a lot of different fillers, trying to find the miracle product but always go back to good ol' Elmers wood putty. I am not crazy about the terrible NON air tight lid, but overall...it's a good product.
Because the lid is so bad I sometimes put a few drops of water inside before I put on the lid and use a rubberband to keep it tighter, but the best tip...just buy the small containers and put it in one of your own nice air tight containers. Lasts MUCH longer.
This is another product that I really like too. A few months back I was standing in the "filler" isle at Lowes and stuck up a conversation to two of the nicest old men who have been refinishing for years. You can learn so much from older people who have years of experience! And I love how they usually stick to the old school methods.
These gentlemen highly recommended this product, Durham's, for filling in deeper holes. I LOVE that it will never dry out and that you can mix up as much or as little as you want. I almost ALWAYS add too much water, but that's ok...just add more powder! I think what I like most about it is that I love making little concoctions:) I usually make too much and when I do, I run around my shop patching up everything I can see on other pieces that might need it too. Hate to waste it.
So remember...A LITTLE water and a LITTLE powder goes a LONG way!
Because this stuff dries FAST and HARD! It is perfect for that first coat of filling in old hardware holes. I always to do a good first coat of this, getting it deep into the holes, not worring about it looking good yet, and let it dry, which does not take long.
I have learned that there is no sence in trying to get the holes filled in perfectly with one coat of any type of filler. It usually sinks in a bit or has air holes. Best to accept the fact that it is a two step process and do it right.
Another tip that might help...I like to use a straight edge of some sort (scrap wood) when filling in an area that is on an end or edge. Just butt up the wood to area that needs filling and use to keep the filler nice and even. Elmers (and not Durham's) works best for edges because Elmers is less brittle.
This nice clean edge is easier and faster to sand out evenly.