The R vs S (synthetic) - Synthetic type may be less benefit.. so best to get non S..
Info--
R-Form Alpha-Lipoic Acid vs. S-Form Alpha-Lipoic Acid | ConsumerLab.com

There are other antioxidant and anti-inflammatory supplements that may be beneficial.
antioxidant and anti-inflammatory supplements at DuckDuckGo

A good resource for checking brand ratings..
ConsumerLab.com - independent tests and reviews of vitamin, mineral, and herbal supplements | Consumerlab.com