oh be nice...

without knowing more about your Raleigh it's difficult to say, nice older roadbikes can make excellent conversions... lighter wheels/better hubs can make a huge difference. If your Raleigh is a cheap model, perhaps an upgrade would be in order...

I'm not familiar with the recent entry-level fixed gear options: people seem passionate about their steamrollers, and Kilo TTs look to be nice frames for the money.

Even if the Raleigh isn't superlight, if it's a higher-end model you might be better off looking into parts upgrades... wheels may make the most noticeable difference.