I like to use 3M Platinum Plus. I use it both at work and at my personal shop. Its pretty cheap from the local supplier, has very minimal pin holes, is easy to sand, and sticks to bare metal, primer, and OE paint. Rage Gold and Extreme are also good choices. I don't really like Z-Grip, its a lot heavier and doesn't sand as well as the "gold" fillers. I also never use 1k glazing putties or icing or anything without a hardener. Evercoat metal glaze and 3M Platinum Plus finishing glaze are my top choices, and both can be used to cut your filler just like Mud Honey or similar products.
I get a lot of products from TCP Global, too. They often have much better prices on things like primer, clear, reducers, catalysts, etc.. They carry a lot of Evercoat products for a good price.