Flight testing suffered a tragic setback last October when Virgin's Enterprise spaceship broke up in flight over California's Mojave desert, killing one of its test pilots.
Newsnight has spoken to several Virgin customers or "future astronauts", two of them on camera.
One, Norwich-based Richard Burr, says he was originally told he would fly in 2007 or 2008, but is sympathetic to the company and has no intention of asking for a refund.
Another, Texas stockbroker BJ Bjorklund, told Newsnight that doubts about Virgin's ability to succeed in getting its customers into space caused him to decide he was "just going to back out of this programme".
Mr Bjorklund, one of the company's first 100 "founder astronauts" got his money back late last year.
After the October accident, Virgin Galactic chief executive George Whitesides said the company would be flight testing its replacement spacecraft by April 2015.
This hope has not materialised either and even plans to resume flying trials before the end of the year now appear to be in doubt.
Asked when the company might get someone into space, Mr Whitesides told Newsnight: "I am hesitant to give a specific date because I want to give our flight test team the time that they need to do it right."
The company insists that safety is its paramount concern. Many test flights will be necessary before paying customers fly.
As to when that commercial service might actually be ready, one former Virgin Galactic employee told Newsnight: "I can't say whether it will be two years or whether it will be fiveâ€¦ They have a huge, huge, way to go."
A customer who did not want to go on camera, and has not yet asked for a refund, told Newsnight: "Like most customers we're really not very confident" that the spaceship will fly as advertised.
But he said he wouldn't ask for a refund "until there's absolutely no hope".
A report by the US National Transportation Safety Board on the causes of Virgin Galactic's accident is expected imminently.
There has been speculation about whether the crash resulted from pilot error or a fault in the craft's braking or "feathering" system.
Asked whether Virgin Galactic has made changes to its new craft in anticipation of the NTSB findings, Mr Whitesides said its design was "basically the same" as the crashed Enterprise.
Mr Whitesides told Newsnight that the precise amount invested in the ambitious plan was confidential but amounted to "hundreds of millions".
Doug Messier, editor of the Parabolic Arc space blog, has told Newsnight that $600m (Â£392m) of Virgin money has so far been spent.
A further sum of up to $380m has been made available by UAE investment fund Aabar.
Mr Messier says: "This programme's claimed four lives already and it's had four powered flights and they haven't gotten anywhere near space in 10 years."
In addition to the test pilot lost last October, three engineers were killed in an accident on the ground in 2007.
Virgin Galactic's planned commercial space service may still be years away from taking flight, and its chief executive admits, "we've got work to do, that's for sure", in a Newsnight report on the project.