You have to remember that many users only seek out these forums and post when they are experiencing problems. You rarely, if ever, see users starting 'DreamHost rocks!' type threads. This tends to create a overall negative slant.
Having said this, at present there is a very real speed problem being experienced by some users on some servers. These users are seeing slow upload and/or download speeds from their sites.
This problem is not apparent on all DreamHost servers. For example, the server my sites are on is still fast and responsive and I have not experienced any major problems.
My advice would be, if you are interested in trying DreamHost, would be to sign up and test it yourself. If you are not happy with the performance you can always take advantage of their 97 day guarantee.
I should note that the guarantee does not apply if you pay using PayPal.
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