You will like the Xb90EX. I don't know what the MHC1 sounds like, but IIRC DSnuts said that it is similar, but the sound should be bigger overall. maybe DSnuts will chime in and give some info :)
two things to consider though : stock tips that come with the XB90EX really are a bottleneck for the sound and Burn in Helps a LOT! burn them in long and hard :)
Which tips would you recommend? I think someone mentioned something about auvio tips but they seem to be a radioshack thing and thus are not available here in germany. I was considering something from comply because I always preferred foam and they are mentioned in the forum quite often.
Apropos tips: the tips from the MH1C are really fantastic! Other mentioned they are worth the price alone and I would tend to agree. Great fit and isolation.