Like Ionus said, Mechwarrior: Living Legends is your best bet until legal issues are resolved with MW5.

There are tons of youtube uploads of gameplay, and you can check it out for yourself at mechlivinglegends.net.

http://www.youtube.com/watch?v=l9ovauSV8Js

http://www.youtube.com/watch?v=5uxx6yHSGj8

http://www.youtube.com/watch?v=kKLpq6AOa44