08 TM250, 08 CRF450R, 06 YZ125, 07 CR125, 10 KXF250, 09 YZF250 and a couple more I've forgotten about.
The only one that I think is worth piddling on, is the YZ125.
Notice that the Euros who are serious about enduro bikes are sticking with steel - and the way TM's WEC/EWC fortunes took a dive around the time they switched to aluminium...
When I bought my "new" MTB in 2005, I did a lot of research to get one with geometery as close as possible to my old chromoly Diamond Back. Ended up with a [Jim] Felt with an aluminium frame.
What a fugging shitbox!
Where the old one tends to be stiff and harsh at low speed, it all comes together as you get the speed up - the springiness of the chromoly starts working for you and it all starts flowing.
The alumium one starts off feeling dead at low speed, but as you pick the speed up, it feels.... dead.
Same basic story with dirt bikes - while they're better than the old 97 CR250 railway tracks, the newer aluminium-framed bikes lack the feel of a decent chromoly frame. My Husky 150 is the best handling bike I've ridden, despite the suspension not being properly sorted (it's close). The Beta 350/400 is a very close second.