I would say the GT2860 will be better for a road car, I drive mine everyday and unless your keeping in the powerband its not the easiest turbo to get on boost as it is. Increased lag with the GT2871R for only pure top end power. I would say it will be more driveable on the 2860 but if your chasing power figures or doing mostly track days then go 2871R.
Worst come to worst, its not the hardest turbo to remove if you feel like an upgrade in the future, and you won't have to change 'everything' as someone has suggested.