Ive just never found a really good TKS system on and aircraft. Hot intakes and leading edges for me every time!
I have prop-only TKS, which works magnificently. Never had any ice on the prop (as far as one could tell) or the windscreen. And it costs little - 2 litres of the stuff lasts 1-2hrs on max flow (I don't use the low flow setting) and costs about £20. I get through ~2 litres a year, running it always in IMC below 0C.
The full TKS system, now costing ~£30k, is reported as similarly effective, and effective way beyond any certification limits, but maybe it is airframe dependent. It also avoids bridging, runback ice freezing, and punctured boots
It also costs a packet, getting through some £200 in an hour, potentially. It's not an enroute solution, for that reason.
bartonflyer - didn't the examiner warn you well in advance of entering IMC conditions, so you had time to turn on the TKS? One "cannot" just turn it on when there is already a buildup, supposedly (though I gather that usually does work). I have my JAA IR test sometime soon and will need to sort this out, otherwise I will have to fly the entire test with the prop TKS running on full bore.