DOCTOR DIFF REAR AXLES

Anyone here ever use Doctor Diff. rear axles ? Are they strong enough to run slicks ?
Getting ready to get dart on track 499 rons toilet Dr Diff Spool(yukon) Dutchman axels and Dr Diff 4:56 gears DANA 60! We shall see! Have nothing but good things to say about The Doctor!!!!!!! He walked me through the whole rearend make over. Thank you sir!