Let's explain a bit more, shall we?
The XTS-3000 is the older member of the XTS-2500, XTS-3000, XTS-5000 line. It is basically a repackaged Astro Saber, which is a darn good radio if you don't mind the form factor. You can pick up an Astro Saber with P25 for $150 these days.
Both the XTS-3000 and Astro Saber are no longer supported by Motorola. Getting parts for them can be difficult (though, given the price, you can throw it away if it stops working). They are both harder to program and require BOTH a cable and a RIB. This is not convenient.
The XTS-2500 and XTS-5000 are both current radios, supported by Motorola. The XTS-2500 is significantly lighter and smaller. Carrying around an XTS-5000 is like carrying around a brick. These radios do NOT require a RIB to program, which is a good thing.
ALL these radios can ONLY be programmed by computer software. So, if you're hanging with a buddy who has a ham HT, and you both want to access a repeater that neither of you has programmed, he'll just tap in the repeater frequency at CTCSS... you better have your laptop and cable with you.
Having SAID that, the XTS-5000 is often available second hand with the options that will allow "FPP", AKA Front Panel Programming. This allows you the ability to enter frequencies from the front keypad, similar to how you can with a ham HT. 99.99% of the radios that are sold with this capability have been "field upgraded" (cough, cough) to include this feature. You should understand that if you DID ever have to send the radio to the Motorola repair depot to get it fixed, it'll probably come back to you without that feature. A local dealer might be fine working on the radio, or they might not. And, of course, you might be able to find a technically savvy "friend" via the internet who can trust to work on your radio for you.
All of the XTS line work well and will take a ton of abuse. It's soooo nice not having to worry about getting your radio wet, or worry about dropping it and having it fall to pieces.
I hope that helps,
Peter
K1PGV