Need advice for non-profit in China Drupal use / big enough

Hi,

I am using Drupal 6.x and currently on a howst at esosoft. I am getting kicked out of esosoft because drupal is killing their server, using too many resources. I am a poor teacherwho is trying to create a distant learning project by myself. I have 1000 registered users, which will double and grow much larger this year. I have between 60-180 users login at the same time, and at around 75 users drupal dies all the time on my shared server. I let my students do their final exam on drupals quiz module, and the site is not open yet, but I anticipate haveing between 300-600 simultaneous users in the future and more.

I have never tried linux, but the tutorials look helpful, and I am interested in the pantheon/mercury thing, which from what I understand doesnt work with ngix. I know linode has an 80 us dollar a month package (A lot of money in China) and I think that is all that I can afford…is that going to work for my site you think?

I dream about the rackspace cloud hosting after watching the san diego drupal con and it looks like they are really one on one with pantheon… but I cant affor 150 us dollars a month….

So which linode should I use? Or is there a rackspace option which is better?

Thanks

Robert

thecenterofthenet.com (down and expelled)