Flashing ICS ROM on GB ?

[theunicodeful]

I've SGS2, is it possible to Flash ICS ROM over my checkrom HD v6 ROM which is based on Gingerbread ?

I need latest either ICS OR GB based MIUI ROM in terms of your Experience with performance and Battery Life. Thank you Androidforums!!

 

[Hawker]

So much for putting in back to Gingerbread KJ2!