How compatible were "MS-DOS Compatible" machines?

[Fred Cisin]

> > MS-DOS was NEVER sold retail until 5.00.
>
> > Any copies that you bought before that were either developer support,
> > through a computer OEM, or gray market.  (grey market outside of USA)

On Wed, 30 Jan 2008, Eric J Korpela wrote:
> I think you meant to say "NEVER sold retail under the Microsoft brand
> name".  You could certainly find "branded" MS-DOS on store shelves
> well before MS-DOS 5.  I've got a copy of "Phoenix MS-DOS 3.31" in
> retail packaging, complete with way to hang it from a pegboard hook.
> I don't know if Phoenix (the BIOS makers) were violating an agreement
> in packaging it this way, or if the store I bought it from was doing
> something shady.  No computer purchase was necessary to buy a copy.
> Just grab it and bring it to the register.  I think that counts as
> retail.

Gray market IS often retail.
Valid, legitimate copies from a user perspective, but NOT explicitly
authorized as retail.
Those "branded" copies were not sold under the MICROS~1 brand.