IR Code formats? Which to use?

Hello! I am trying to create a program in vb.net and I want to send IR signals to the remote device. I have two possible types of strings for the IR codes.
One type I can use looks like this: $89 or $8E
They appear to be simply hex numbers.
The other type I can send are like this: R080081028085208085202121808620212180862022212121
I can use either one. Which is preferrable and what format do I set the
gIRCodeFormat to? UUIRTDRV_IRFMT_UUIRT or UUIRTDRV_IRFMT_PRONTO or something else?
One type I can use looks like this: $89 or $8E
They appear to be simply hex numbers.
The other type I can send are like this: R080081028085208085202121808620212180862022212121
I can use either one. Which is preferrable and what format do I set the
gIRCodeFormat to? UUIRTDRV_IRFMT_UUIRT or UUIRTDRV_IRFMT_PRONTO or something else?