I love my 510, it will work with a DP system. As long as the system isn't a lease they will activate it. Just get the R00 and S00 number and call Dish to see if its a lease and if there is a balance on it.
If you're an AEP subscriber, you'll be able to provision it with no problem and no extra cost except for the normal receiver fee. If you're not, you'll have to pay an additional $4.98 per month on top of the receiver fee for the bs VOD fee.