I have done beautiful sculpting with Bellafill. The jawline looks amazing. I would highly recommend it if you know what you like with HAs in the jawline.
Bellafill lasts for 5 years and up. I have patients who have been treated 7 years ago and are still thrilled! HAs do not last more than 6 months. Especially for people with high metabolism. That being said, Bellafill is not recommended in the tear troughs unfortunately
You will need t have a skin test before Bellafill to see if you have allergy to the bovine collagen. Lumps and bumps are common with ALL fillers. If you look at Bellafill studies, it has low rate of adverse reactions. I would not worry about bumps and lumps with Bellafill.
The carrier for Bellafill PMMA is collagen which does not last. It's only there to take place while your own collagen grows. You will see full results in 16 weeks. It is normal for the injection site to decrease in volume while your own collagen is building. Especially for people with high metabolism.
Bellafill is an amazing product. It lasts for 5 years, so patients love it. It has also been studied heavily and studies show it has a great safety profile. You may be referring to Artoplast and Artocol which were older forms of PMMA which caused issues and were never FDA approved. You do not need surgery to remove Bellafill. There are other ways of minimizing it.