I have been going through different fillers like crazy lately, ,I have been a platinum user for quite some time, but lately I have been looking for something different. I feel like platinum has been changing, It's still one of the best out there but it just seems different, I have been getting more pin holes with it lately than what I did in the past.. I gave the new 3m select recently and I really liked that as well, then the automotive art fillers, their platinum is pretty good. Then recently I tried the rage ultra and ultra extra.. Everybody in the shop now prefers the ultra and ultra extra.
The ultra extra has a very long work time. You can spread it for over a half hour, it's a very slow drying filler.. The regular ultra is fairly quick drying. You can mix the two to get the dry time you want and that works really well for doing a full car. I noticed we have been getting less pinholes, and it seems to sand better.
If you are doing a large panel, mix them half and half. You get a good work time, but there is that sweet spot with filler where it sands easy.. This window is drastically extended when you mix the two. I can sand a full fender and the filler will still sand really easy. after about a half hour of sanding it starts to set up really well.
WARNING: We had a few batches not cure.. Event left it sit over night. What I found out is that if you use a different hardener than what comes with it, it may not cure.. the ones that come with them seem to be stronger. I think we scraped it off of 3 sections before we realized what was going on.. I even talked to the FE rep and the first question he asked "did you use a different brand of hardener" My answer was yes.. I'm not use to having all of these different filler hardeners.
Automotive Art for instance, has it's own hardener. with their line you only use about half of the hardener, if you use to much it will spread weird and start setting up really fast.
I have always had bulk hardeners in my store because you could use them in anything I carried. Well apparently things are changing and you can't do that anymore.