I have a MTM 3piece suit from SS, measures have been taken in Antwerp, alterations are being done in Brussels. The suit is not perfect but better than most I have bought so far (Hugo from Hugo Boss).
I asked for the suit to be fitted as tight to the body as possible, tight waist, narrow arms and trousers, no pleat. I would have liked to alter the lapel width (narrower) and hight of the notch (higher) - both was not possible due to their production process. Within limits I could have the closing button moved (downwards).
I have chosen flap pockets and peak lapels but would have preferred a ticket pocket and to have them slanted, which was not possible either. For the moment, you can have a notch lapel and ticket pocket or peak lapel and two pockets. These were the limitations to their customisation options which I have noticed. How many measures they take to alter the standard model for MTM I do not remember but I can recall that the shoulders and arm holes were narrowed, the jacket length was shortened, the trouser's waistband was lowered, and of course length of trousers, sleeves etc.....).
Their advice here was very helpful, as the staff in general is very friendly and helpful. I had told them what I had in mind and showed them one of my favourite suits, they did the measuring, let me choose the customisation options, asked for my preferences on some of the less obvious choices like jacket length and hight of the trouser's waistband and took care of the more technical issues.
After six weeks the suit was ready for trial. The look was good but a number of alterations were obviously necessary: The waistcoat needed substantial tapering, the trouser legs had still to be made narrower, the bottom adjusted, jacket sleeves were shortened, the waist let out by a tiny bit and there was too much room at the collar.
I tried the suit a second time after the alterations had been done and with the exception of the waistcoat it does fit well now, whith the exception of one or two details that seem impossible to be changed. I might ask for a second opinion by my alterations tailor here.
All in all, I am happy customer for the moment. I will pick up the suit after the waistcoat will - hopefully - be good on Monday. But then, the suit has yet to stand the on-road test.
If there is interest, I will keep posting.