In airsoft, an Offset mount limits the range you can use the red dot a fair bit more (out of the two options), but hey if you're certain you'll only use it very, very close and you think it looks cool then why not.
The very large distance between bore line and red dot with Piggy is a lot less of an issue in airsoft than firearms, and you never induce a hop issue, but still might need to aim high when very close and going for a small target.
3rd option is save money and weight on the gun by using your optic 1x or just point shooting under ~15-20m or so using the classic cheat of every white bb being a 'tracer'. Build might not look as cool though.