I have two non-inverter 900 Btu/h Haier units in the bedrooms which are still working after over 8 years. To be fair I hardly ever use them. I also used to have a non-inverter 1200 Btu/h Haier model in the living room but that wasn't up to the job at all. Nothing basically wrong with it, just not powerful enough. I was recommended Haier if we wanted a lowest capital cost solution but was told they would be more expensive to run.
I changed the living room unit a few years ago to a Toyotomi inverter model. I'm not sure if it is the 1,800 Btu/h or the 2,200 Btu/h model but it is much better than the non-inverter type. I think the GAN/GAG-A 180 GVR currently cost around €650 while the GAN/GAG-A 240 GVR is around €675. Fitting would be extra. There is a spec sheet on Page 19 of http://www.toyotomi.jp/manual/catalogue ... oner13.pdf
Unfortunately it is in Greek but you can easily see the figures for SEER, Seasonal Energy Efficiency Ratio for cooling, and SCOP, Seasonal Coefficient of Performance for heating, plus the ratings, e.g. A, B C etc. The higher SEER and SCOP and the lower in the alphabet the rating then the cheaper it is to run.
I think Toyotomi are a good make but I think it is possible that Fujitsu and/or Mitsubishi make higher efficiency models but possibly at a higher capital cost. Worth investigating and checking out the figures. As an example the Mitsubishi MSZ/MUZ-FH35 is only 1,200 Btu/h and costs around €1,000 plus fitting but it has higher SEER/SCOP figures than the Toyotomi range. How long it would take you to make back the extra capital cost would depend on how much you use it.