You will need to define 'good ass plan with everything on'
Seriously though, the major difference between the plans is the storage space and bandwidth quota offered. The level 4 plan does offer a unique IP address, SSL certificate, VPN access and a 'free' copy of Miva Merchant, but if these are not important to you then you can make your decision based on the quota offered by the various plan levels.
I should also note that the level 1 plan does not include any support 'callbacks' (valid for US customers only).
Overall, I think you should study the DreamHost plan comparison page and make your decision. Remember, as others have said, changing plans (at any time) is extremely easy at DreamHost.
Note that you will have a 97 day money back guarantee (minus your initial 'free' domain registration) if you pay by credit-card or Google checkout.
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