Removal of synthetic medical mesh ?

I guess the trouble is you haven't finished your reconstruction so how it will be when finished is unknown. Yes it may well be affected by the radiotherapy but during change over surgery this may well be sorted. The pain may be the pocket shrinkage from tbe radiotherapy. The pockets are often cleaned up at this time to improve the space.  The option may also be to replace with acelluar matrix at time of changeover. It will feel uncomfortable again until the stitches dissolve and movement improves. 
I'm not saying you shouldn't go flat...I'm just saying you can't guess the final look, feel and comfort by what it feels like now straight after treatment and still with an expander in.