Identifying the "best" would require knowledge of multiple factors. You can do your own research, here are some to look at:
Vapor degreasing: DuPont Vertrel specialty fluid, various suppliers of n-propyl bromide
Detergent cleaning: numerous products from multiple suppliers, e.g. Henkel Parco Cleaner 800 or Chemetall Gardoclean S 5065 or SurTec 199