Stainless replacement bolts in engine front cover?

I think I heard it is not a good idea to replace the bolts on the front of the engine cover with stainless steel? Is that the case? Has anyone done so - successfully or unsuccessfully? Wunderlich have them with black heads which look neat.
Many thanks
LBJ

Probably because of bimetallic corrosion https://en.wikipedia.org/wiki/Galvanic_corrosion
Personally I have replaced most of the nuts and bolts on my bikes (and sometimes cars) over the years with good quality stainless fasteners and never had an issue. I usually use ACF50 grease as it's supposed to be a "corrosion block", but in the past used copaslip. There's also a special "grease" called "Duralac" which is specifically designed to work in these circumstances.
Personally I would buy the stainless fasteners if you like them, and install as I suggested (Duralac, ACF50 Grease or Copaslip) and i doubt you will have any issues.
My 21-year-old K1200RS has dozens of stainless fasteners and not been an issue for 21 years!
Chris Shaw does great kits (incl odd sizes for BMW's such as oil drain plugs) https://www.shawstainless.co.uk/
Stigs is another favourite (he does Land Rover kits) https://www.a2stainless.co.uk/
Corrosion Block Grease http://www.acf-50.co.uk/corrosion_block.htm

35 years of owning bikes and always used stainless bolts without any issues.
Just be careful if looking at high tension areas (Brakes etc) as these are usually a “different spec”.