The Premium is permanent or yearly? If it's a US/North American one it should be annual for that premium. If it's from somewhere else in the world it may be permanent? 

I wouldn't pay more for one that has something you can buy for like $800 yearly on the cheaper 4640. You could buy the cheaper one and some year down the road if your 2630 is down call the dealer and add a year of premium and you're back to having RS and SC and such