Mady the company didn't go bust but HSL stopped using them because the wires kept braking due to bad design. My colleagues still have them but out of the three who wear them only one still can since HSL no longer repair the in ear plugs.
There are some excellent Danish ones which also negate the microphone but they cost £1k. Have a look on here there is a thread about them.
I think Helmet plus in ear is the best you can do nowadays.