Free vs paid mock platforms — honest comparison

I've used Testbook (paid), Adda247 (paid), Oliveboard, and now trying Shishya. Testbook has the largest question bank but their mocks feel formulaic. Anyone else compared?

Shishya's adaptive feature is genuinely different — last 3 mocks were all on my weak topics. Testbook's mocks feel like they're sampled from the same pool every time.

Adda247 PYQ database is unbeatable for SSC. Their AI mocks lag though. Mix-and-match is the play.