I, too, can personally vouch for HTG. I got my 600w system from them, along with a fan to cool the bulb. When they were out of the upgraded bulb I requested, they sent me a different one, then within days they sent me my originally ordered bulb, along with a note saying to keep the other one as a backup. The customer service is what keeps me coming back for just about any supplies I need. Shipping was quick too...
Peace...j.b.