[Coley]

Ok, so you already have the motor so you are already committed.

If it was me, I would drive it for 3-6 months and then solve whether or not I was happy with the performance and if it felt 50-75hp stronger than my original motor, etc.

Now for me (and we are all different), I would want it mostly on take off and in the lower range...up to 50mph.
Now, if the 290hp simply didn't feel like it was putting out....I would then spec a new cam to put in it...and I wouldn't worry about the 'warranty issues'...and the odds of the engine failing are low if the swap is done well.
The cam I would pursue would focus more on lift and lobe separation than duration. So I would be happy for forgo the 'lumpity lump, long duration sound for the performance at lower speeds.

Regardless, drop it in...fire it up and take it for a drive and let us know what you think.

All good
Coley