There are a number of related threads on this matter.
Any frequent HSDPA Users in the UK? provides some users experiences.
UK Mobile Internet Use for an Australian Visitor for 2, 3 or 4 weeks gives some casual use advice. OQO is coy on its inbuilt modem
specifications instead giving a knowledge base topic 'e2 HSDPA 3G mobile broadband FAQ' answer to the question 'What are the uplink and downlink speeds for HSDPA?' of 'The maximum downlink speed is carrier dependent. According to the Global mobile Suppliers Association (GSA), typical user data downlink speeds are 1-3Mbps, although many carriers already supporting maximum downlink speeds of at least 3.6Mbps. Maximum uplink speed is 384 kbps.'
I suspect the OQOe2 modem could not support 7.2Mbps download but no one can say where an unlocked
Huawei HSUPA USB Stick E170 can be purchased.
Links to any commercial and technical reports on this matter would be appreciated.