which XM Sat radio seller to go for?

You do have to take the dash apart with Coastal also. But not as much as it shows in Coastals instructions. Glove compartment and panel to the right of the radio plus the kick panels on the right front passanger to run the cable. Plus the computer under the panel to the right of the radio must have a 10mm bolt removed to get at the back of the radio. It is this computer that is the reason for glove box removal - so you can get at it and the radio back side.

I bought from Coastal because they had a free years service and free activation at the time. It is the 2nd time I have seen them have that sale. It makes it a really good deal. If there is no sale however, and the prices are equal you might go with PriusXM as I understand the DVD instructions are first rate. I got by fine with the printed instructions and CD with pictures from Coastal.

 

Oh, the systems are the same. The install location of the XM box may be different, but I am not sure. Online ordering might be better at PriusXM as Coastal has a very bad reputation for not responding to emails or confirming purchases. If they are out of stock, you might not even hear from them until it ships. So far my three purchases from them have gone fine. I would like to recommend them as the best, but they need to fix the order, confirmation and stock status part of the business.

 

I got mine from PriusXM, and would recommend them for the DVD alone. I have dealt with Costaletech on another order, and they were as slow as has been rumored

Here are photos shat show how to avoid taking the driver side dash apart and my center mount take on the antenna:

http://priuschat.com/index.php?showtopic=11058

 

Although what you've selected is probably the best if you want the integration (which is great) an alternative is a portable like the Roady or the xm2go. You lose the integration, but there are some gains. The xm2go works at home, in the car and by itself and will record up to 5 hours for later playing.