Ok, for a moment let’s take the rare possibility that you have exactly the same gear as the Creator of the preset you bought. Same Amp/Cab for example, even same guitar. First of all, we have to agree on one basic thing:
Listening to a recording from your speaker/headphones has, and will, never have to do anything with being in the same room as the player or more correctly the cab used and listening to the live sound. What you hear in a demo, whether it is a youtube video (mp3) or at best a soundcloud audio file (wav), is the capture of one or more microphones and the analog to digital conversion of the sound via some audio interface, hopefully without any post effects. So what you basically hear is how someone would record this preset with some specific mics in specific positions/angles.
If you have a good sound, as close to the desired mix as possible, then a good sound engineer would be someone who would successfully capture the sound as close as the real one. And that would be the target, because attempting to capture the real sound (meaning how a person in a specific position in the room would hear the live sound) will always prove unsuccessful no matter how much technology evolves (hopefully I will be mistaken about that in the future, but that would definitely be a distant future).
Technology has evolved that much though so as to give us the opportunity of using that capturing method in a digital form. That would be an Impulse Response or alternatively an IR Cab. When using an IR Cab we have to always remember that this is a simulation of one or more mics placed at a cab. And that’s why using any Cab Sim always gives a different feel to the guitar player because it tries to mimic what that player hears from the sound captured by one or more mics placed at a cab in a different room than him. It will always be different than what the guitar player hears when he is in same room as the cab.
Since we solved this, let’s go to the other possibility. Using the preset with an IR Cab. In this case you should always check your signal chain. Something we should always remember is the amount of impact each intermediate item has in your signal chain. And that would be the opposite of the direction of the signal coming from your guitar. So even if you have a different guitar for example, it would not make that much of a difference as a different FRFR speaker, PA console or audio interface etc.