The instructional videos here are amazing. My recommendation to you would be to pay for the Diamond for one month, and watch a lot of the videos, and try chess mentor. If you like them, you can stay with Diamond, but if you don't find them useful, you can go to Platinum.
I know that for me, the videos are well worth the extra price. The King+Pawn endgame series, Rook endgame series, Material Imbalance series, all the Live Sessions, Pawn Structure 101 series, and many more have taught me a great deal.
If I am posting this in the wrong spot please move it somewhere else for me, thanks.
The Diamond membership is twice the cost of platinum however only offers about 2.5 extra bonuses as compared to the platinum membership, so I ask is it really worth it, doubling the cost but the few extras giving the learning edge compared to the other memberships?
Thanks for taking the time to read and reply.