I have converted all of my fluorescents to LED. I just wired directly to the tube(s) as instructions, re-using the wires within.
It might not stack up economically but the joy of immediate illumination and no buzzing and farting is worth it for me. Not sure about the life yet but not sure about mine either!
There is only one thing to watch out for – the replacement LED tubes have to be set vertical i.e. the prongs have to be horizontal when in use. There are a few old fittings out there where the prongs are vertical when in use – it didn't matter with fluorescents which way up they were. If you have one of these you have to change the fitting.
Neil mentions LED replacement bulbs – I changed from the so-called energy efficient tube type which take half an hour to get to full brilliance to LED and, just wonderful. Great pleasure when throwing the old stuff in the bin.
Just my opinion – we all see life differently, but no downside for me.