We use a lot of 2924s. They are a good switch and you should be able to use them for a long time.
The deal at the moment seams to be Extreme Networks Summit24s though. We have just purchased a lot of them at a very reasonable price. They have a TON of functionality too. Something that would make a good network core device for a while. By the testing I have done so far I woul feel pretty good putting a few gigabits/sec through them. They have a GBIC port so there is some flexability. They also offer layer3 ability. (Limited to RIP or static routes unless you buy a $1400 license.) There seams to be a lot on ebay for a few hundred each at the moment.
We have hammered on extreme networks equiptment pretty hard for a few years now.. It has been holding up very good. I have a couple of BlackDiamnd 6808s that I absolutly SWEAR by. very sweet units. I hav dreams about the BlackDiamond 8810.
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