Personally I feel the changes in the end are debatable, I know I'm in no hurry to change. I'll wait for their new model
to replace the MK2 and see, well hear.
1. If you already own the non MK2 version the MK2's are not substantial, differences yes but in no way makes the non MK2's sound broken.
2. I have found the height of performers is lower with the MK2 version, I personally prefer the non MK2's in relation to this but you could always raise the MK2's.
3. The extreme top end is different, I prefer the non MK2's. Possibly something to do with the cross over re-work.
4. Bass is slightly better with the MK2's but add some subs with the non MK2's and well ....
I would not be worrying. Spend that money else where in the chain feeding your speakers or on music, will be more beneficial and just enjoy!