What does the book call for as far as the install time? Most reputable places will go by that when quoting you a price, even if you think it should take less.
If it's 7 hours by the book, then I would not expect miracles where a good shop will just do you a solid and only charge for say 4 hours. If the book is less than 7 and those guys quoted you for 7, then again any legit shop will go by the actual book hours. It also comes down to what you need to do, if you're buying the front struts already assembled or not.
If you haven't called these guys yet, I would start first with Fastrack in Peabody.