I have the opportunity to buy a used f113 from a guy that works at the stereo store for $2,600. Otherwise I could get a new f112 for $2,350 + tax =$2,490 or a new f113 for $2,890 + tax = $3,060. Unit is in good shape, used about one year, don't know anything else about condition. All satin black. Rest of system will likely be Denon 4308 running Paradigm Studio 100 v4s, CC-690, ADP-590s. Room is 20W x 30D w/ vaulted, listening position 9' from speakers. Thoughts on which one I should buy and why?