I posted a dyno graph somewhere in one of the whipple threads here. I don't remember what it made - no where near what the blower is capable of with some supporting mods and a tune.
The tune is definitely on the 'soft' side, but for a DD it's just fine, too much more would get dicey if you weren't paying attention. The hp/$ is pretty steep until we can tune, but it was worth it for me and would do it again. It's a blast to drive. If I had to describe it, it's a lot more power midway through the powerband, and then it eases up a bit up top (which is the nannies trying to keep you from breaking stuff).
I have a whipped '19 5.0 with tune, e85, injectors, fuel system, etcetc and it's objectively faster in the 1/4, but also a much harsher driving experience. I still drive it when I want a rowdy ride. But man, the R with the whipple is so smooth applying power, and I don't have to watch gauges to not hurt anything. I'm enjoying it while I can before I mod it much further and it becomes a race truck instead of a DD like my other truck.