The LSA's are going to be the way to go for Private training. Cessna's will probably go into production next year and it will be less than $100k brand new. The panel is slated to be LCD displays that show a six-pack. You won't be able to do instrument flying in them, but I think they're going to be awesome for Private training. I would imagine the rental rate would be around $70-$80/hour, which is exactly what this industry needs again - more affordable flight training in new aircraft.
I've been flying 172SP's and R's for 4 years and I've never had an "engine stumbling" problem that paulsalem mentioned. IO-360's aren't the smoothest running engines in the world, but they're very reliable. The interiors are no better or worse than new Pipers or Diamonds. They all have their quirks. For me, I don't think there has ever been a better training aircraft out there than the C152 and C172. They're built tough as nails, they're easy to fly, and no other GA aircraft manufacturer comes close the Cessna's support network.
I've got quite a bit of time in a DA20-C1 Eclipse too. They're good airplanes, but they don't seem to hold up as well in the training environment. Also, if you're in an area where it gets really cold, they accumulate frost on the wings much faster than aluminum planes. I don't know the reason for this. It's not a comfortable airplane for larger people and the CG range is quite narrow. It's a good plane, but it's not something I would want to fill up a flight-line with. It's more of a weekend warrior aircraft.
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