Yamaha chipsets do not like games that use the ADPCM features of Creative's DSPs. Thus certain sound effects in Duke Nukem II will not be heard, but that is the only game I know of that uses the ADPCM features of the Sound Blaster cards.
As far as the Sound Blaster Pro goes, you lose the UART MPU-401, the gameport has no system speed sensitivity at all and whatever games use 16-bit sound will sound poorer than with the 16. However, so few DOS games use 16-bit sound that the Pro will almost always sound better than the Noise Blaster. I would strongly suggest getting a 2nd generation Sound Blaster with the CT1747 chipset.
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