Javelin,
You will actually find that most of the newer microlights will out perform your said aircraft not to mention half the cost to maintain. It's sounds like a typical GA view to microlights. CTSW, Banbi, and C42 to mention a few, all have sub 120 knot cruise capability on 12-15 litres per hour. You will struggle to get that in a spam can.
I think Javelin was considering spending around £3K.
Whilst the above mentioned machinery may be very efficient and desirable they are all without exception going to set you back in excess of £42K. Some in excess of £50K. Also, I do worry about the longevity of the current crop.