I also have a 4500...good machine...as Tree Reaper said you will have to make some adjustments, as with all machines...One small bit of advice--when you get a thread jam or birds nest under your leather--DON'T just rip and pull the thread lose...take your time and free it without excessive force. I learned the hard way...you will knock the machine out of timing...then you will get to learn a lot more about the machine then you may want, this goes for all sewing machines...they are built like tanks, but treat them with respect and you will be happy for years to come...One other thing, keep them oiled...Oil is your friend.
Just my 2 cents worth.
Troy