There's no question in my mind that, although I haven't heard them, the KAB mods must be a great improvement on the stock model. Re: the mat I simply listened to the two and chose the Rega felt one for both which was handy for keeping the comparison to the tables themselves even though the Rega felt mat would be unlikely to be used with the Technics. There are better/different mats for both tables but I didn't want to muddy the water any more than necessary.
Attempting direct comparisons are ultimately confused at best because optimizing the very important cartridge/arm relationship gets thrown out by using the same cart for both. I used the Exact because it was the best appropriately priced cartridge I had on hand that was broken in. I later put an older Sumiko Bluepoint Special on the Rega to great effect which surprised me that I liked it better in some ways than the Exact. I haven't tried it on the Technics yet.
Attempting direct comparisons are ultimately confused at best because optimizing the very important cartridge/arm relationship gets thrown out by using the same cart for both. I used the Exact because it was the best appropriately priced cartridge I had on hand that was broken in. I later put an older Sumiko Bluepoint Special on the Rega to great effect which surprised me that I liked it better in some ways than the Exact. I haven't tried it on the Technics yet.