Building a semi future-proof CCNP lab

Dephcon

I'm looking to build a lab for CCNA/P, I have access to one at school but its a hassle to get in there and we only get a 2 hour time slot per week (and its at an inconvenient time) plus theres never enough serial cables

The pods we're currently using four our courses consist of:

(1) 2501
(1) 2503 (2 are 2520/2522)
(1) 2610 w/ WIC-2T
(1) 2620 w/ WIC-2T & BRI
(2) 2950
(2) 2900

So i want to build my own lab, but i want it to be as future-proof as possible with the new ccnp certs.

i was thinking of getting (3) 2500s, a 2509, (2) 2600s and a 2950

but since the new ccnp require ios 12.4, will i need to replace the 2600s with 2600XMs later to get 12.4 functionality? Would it be worth the additional cost now to get the 2600XMs? or will better routers (2811) be cheaper in the coming year(s)? Will the 2600s still be useful in 1-2 years? I dont plan to take my certs for another 20ish months (when I'm done school,) but I would like to get a partial lab built soonish, before the fall semester so i can start prepared for the ccnp courses.

Thanks

EdTheLad

You can run the 12.4 2600xm image on a standard 2600, you just cant copy it to the flash,you need to boot from a tftp server to copy the image to ram.So once your 2600 has 64k ram your sorted.Check out Dynamips before splashing out on routers, if you can afford a pc with dual core processor and 4GB ram go that route.
For switching it depends on your budget but you cant go wrong with 3 2950's.After you are near ccie level rack rental is the way to go.
Learn to use the search function as i dont think i've said anything that hasnt been said before.