I love the Hs129 but it is a quirky and underpowered aircraft... problems it suffered in real life.
From Wikipedia:
Hs129B-2
Max. takeoff weight: 5,250 kg (11,574 lb)
Powerplant: 2 × Gnome-Rhône 14M 4/5 14-cylinder radial engines, 522 kW (700 hp) each
http://en.wikipedia.org/wiki/Henschel_Hs_129
Compared to say an IL-2M3
Loaded weight: 6,160 kg (13,580 lb)
Powerplant: 1 × Mikulin AM-38F liquid-cooled V-12, 1,285 kW (1,720 hp)
The IL-2 is a later model cetainly and it does weigh a bit more but it has a 320hp advantage from one engine compared to two. The Gnome-Rhone's are very poor from a power standpoint.
My suggestion is to fly the Hs129 very gingerly. It's a solid attack aircraft and can really kill tanks but it's slow in everything it does. The upside is it's very stable for gunnery as it has a good counter rotating propeller arrangement.