Agreed!.
Keep in mind a 10" weighs around the 14.5kg mark and the 8" 11kgs so the motors aren't really suited for extra weight..
I have a Skywatcher 254mm (10") on a EQ6 and have no hassles at all, the only thing you need will be another counter weight, the 2 that come with the mount are not enough to offset the weight of the 10"
If you are on a budget, My opinion would be to buy a second hand EQ6 which will be cheaper then a new 8" on a GOTO mount. And just wack your 10" on it and used the leftover money on a good set of eyepieces and Barlow. Will get you amazing views
Cheers