I’d say that there’s no question whatsoever that Virgin is the superior product, and especially being quite tall I think you’ll definitely appreciate the extra space, but is it $5000 better? I can’t really make that call for you.
Virgin offer a reverse-herringbone seating configuration in business class, which guarantees direct aisle access for every seat in a 1-2-1 seating configuration, whereas United’s aircraft offers a 2-2-2 seating configuration which is not ideal for those who like a window seat and also means a narrower seat as they’re cramming an extra two seats across. If you’re traveling with a companion (wife, girlfriend, colleague, friend etc.) that’s one thing, but if it’s a stranger who you have to delicately step over in the night to go to the bathroom I’d say probably not.
Both seats will extend to a fully flat bed, with United’s measuring in at 198cm when extended (about 77.5 inches) and Virgin’s measuring 203.5cm (about 80 inches).
As far as the service goes again I’ve always found Virgin to be a bit better, however I flew united business recently and it was fine. Not the most pro-active crew, but the food was nice enough and the booze selection and entertainment was good.
All these services though are all cosmetic; the reason we fly business class is for a comfy bed so you can sleep and arrive relaxed. Virgin’s is better no question for a broader and taller individual like yourself, however again with $5000 difference in it some might and you may be willing to take a punt on another product.
Hope that helps!