We're not happy about it. It will be politically difficult to sell Turkey more arms in the future. Popular opinion doesn't connect us to those tanks, however. We don't feel responsible. We sell weapons all over the place and the best we can do is try to sell it to the "good guys". Sometimes we fail, just like other nations sometimes misjudge a country's intent.
As for the Leopards getting destroyed. Those are Leo2A4 variants. We knew they were shit, that's why we wanted to get rid of them. The A4 is an 80s model. Turkey bought our old stores of used tanks and that's what's getting destroyed over there.
As for what we use, we're on A7 these days. And as an acquaintance with connections to tank division says... "Only an A7 can take out an A7." So it doesn't concern us at all. What concerns us is that we do not have enough A7s to consider them an entire division. We're severely lacking in spare parts and maintenance man hours. That's a much bigger problem than the A4s getting wrecked in Syria. The German army has been mismanaged by imbecile MoDs that want to further their insignificant political career on the backs of our troops. Easily done, mind you, since the public still isn't too fond of its armed forces. It's interesting to see how the shadow of WW2 still looms over us today, if only at a subconscious level. It'll pass over the years, but right now, we're pretty much heading towards rock bottom as far as the army goes.