Yes, both SyncSketch and ReviewStudio offer a Free Trial.
SyncSketch is designed for Large Enterprises, Medium Business and Small Business.
ReviewStudio is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Pricing for SyncSketch Starts at $6.80/Month when Billed Yearly whereas for ReviewStudio Starts at $15/Month when Billed Yearly.
Some top alternatives to SyncSketch includes Ziflow, ProofCafe, QuickReviewer, ReviewStudio, Workgroups DaVinci Proof, Filestage, WebProof, Coment, MediaMarkup and Proofing.
Some top alternatives to ReviewStudio includes PageProof, ProofCafe, QuickReviewer, Workgroups DaVinci Proof, Hightail, WebProof, Coment, CrossCap Online Proofing, ProofStuff and Proofing.