I recently bought a pair of SP-2500 for $120 and they are perfect. There isn't a scratch or blemish anywhere, not even on the bottom of the cabinet. There grills are perfect and there are no tool marks on any of the screws. They are mint. I thought they sounded pretty good but decided to replace the cross over capacitors. I bought Jantzen Audio capacitors from Parts-Express. It made an improvement that seems to get better the more I listen. The highs opened up and the mids are not as over whelming. Definitely a worth update. After replacing the capacitors, I thought I should have made a video or at least taken some pictures. It may seem daunting to some but it isn't that bad. If anyone has questions please ask. Now the interesting part... Even though they were bought together, they are 50,000 different in serial number. The first cabinet I opened was the earlier unit and it has really long base ports. I was surprised they extended so close to the back. I completed the cross over and reassembled the cabinet. I opened the second cabinet and it has the short ports like every SP-2500 I can find has. I wish I had pictures of the long ports. I will take some eventually but I don't want to wear the wood threads by opening them too often. I compared the bass of the two and the long port cabinet can reproduce low bass better then the short port cabinet does. The long port cabinet has a much fuller nicer bass. I used a calculator at http://www.mobileinformationlabs.com to determine the port frequency. I used the following: Cabinet volume: 1.5 cu ft (1.8 cu ft - .3 cu ft for stuff in the box) Port ID: 2.5” Port Length #1: 6 1/4 x 2 Port Length #2: 3 1/8 x 2 Number of Ports: 2 With the calculator I had to guess port frequency until the length came up. I assume the length given is the sum of the two ports. Cabinet #1: 35 hz Cabinet #2: 46 hz It seems like the port length is too short in cabinet #2. Interesting isn't it?