the 2500 is still in production, at least until November 30, 2014.
It will be officially supported by Motorola for 5 years from that date.
This applies only to the "BN" versions with the 8 MEG boards. The earlier production "AN" radios went out of production a few years back and are already no longer supported.
The majority of the eBay low priced 2500s are the "AN" variety. A few things about the older radios: there will be no more firmware updates coming from Motorola. Because the earlier version had limited HOST ROM, new features that become available or enhancements won't make it to the older "AN" radios.
The other point is the durability and serviceability. I've owned many and my employer currently has XTS2500 (both a mix of AN and BN versions) but they are being phased out gradually with APX4000s. The weak point in these radios is the front cover interconnect flexes. This is how the radio's front cover electronics and side connector interface to the main board. These connectors are FRAGILE, and mainly fail due to "Mr. Goodwrench" and his golden screwdriver folks poking around inside. If the radios work, they are fairly reliable.
However, if they are dropped too many times and the connectors develop problems, the radio is pretty much history. Flat rate repair is still available for the BN units, but it isn't cheap ($380 for end users last I checked).
The connectors are impossible to repair and damn near impossible to replace unless you have a hot air rework station and know what you are doing.
Third point: there are many sellers on eBay selling hacked, non-legit XTS2500 and 5000 radios, but the 2500s seem to be a target. Many of these are obvious bogus radios like this one:
Motorola XTS2500 Model III 700 800MHz Portable Radio | eBay
Note that this is an "AN" radio with a fake tag and a serial number with a manufacturing date of 2013.
Here is what someone who had several of these gems show up in his shop had to say about these radios:
"Ugh... I'm familiar with his junk. AN 2500s with a date code well into the era of BN manufacture, extra-whored flash code, glued-on volume knobs. 50 of them rolled through our shop, many failed bench test, including a basic button test. Same user bought some XTL5000s from them, equally junk. Obviously bogus tags, and the radios said last programmed with depot several weeks before they were bought. No attempt made to disguise their use of the forbidden software. "
So 20 people spent $475 on a radio that fails basic BER testing, has glued on parts, and was obviously a scrap parts unit cobbled together and misrepresented.
Always
BUY THE SELLER not the item. It's the wild wild west. Do your research. There are some great sellers on Ebay and the forums, and they are well known.
But before spending hundreds of dollars on a radio, make SURE your seller is honest. ASK for detailed pictures. Check the serial numbers and flashcodes. ASK if it is a legit Motorola radio or one built from parts. Will they accept returns? Do they warrant their product? Overseas sellers may have lower prices, but many of the radios are "accelerated life testing" or scrapped units. Even if they stand behind them, return shipping can be a costly expense you will have to cough up to send back a bum radio.
Don't get scammed.