Basic you can try a seven day free trial.  I think its worth it, but there are other interfaces that offer the same things.  LIKE FICS but its not as user friendly.  Try the free trial first to see if you like it.

I use the Mentor a lot and am enjoying the Video lessons, I definitely think the extra is worth it.  This assumes you will have the time and motivation to use those two features a lot! in 6 months I've spent over 30 hours on Mentor..it has defintely improved my chess skills. The videos are both entertaining and instructive. I reckon if you're going toupgrade go the whole way, platinum really only gets you more tactics and Opening explorer access to everyone's games.  THis last is not at its best right now as they haven't uploaded any new chess.com games for quite a while so all my own games are not there.

another thing to consider is, is what you get for your money, the difference between platinum and diamond is not that much, the video lessons and chess mentor but it is a decision that you have to come too...for me a platinum membership suits me and I don't require the extra upgrade but that comes down to personal preference

I purchased an annual diamond membership last week.  I have already worked through 5 Chess Mentor courses and watched several videos.  I have the Comprehenseive Chess Mentor program on CD, which contains about 10 courses.  This program is fantastic and that alone is worth the price of a diamond membership.  The videos and other features are a bonus.  Of course, as an adult, I have more discretionary money than a teenager.

Thanks VernalFire.

Yeah, I saw that earlier.  I was just wondering if the people who are paying members thought access to these tools is worth the money (being a teenager, I don't really have a big chess budget; and I've already drained a considerable amount on chess books, etc. :P).  It certainly looks like it is, but I'm also easily deceived (as is evident in my chess play!)

Thanks for your help!

If you hover over 'members' at top of page, then left click on 'memberships' it will outline what you get when you sign up for membership, it is your choice then and then you can work out what suits you as to what one you will choose