Hello
My current lab setup is:
2x 2651XM's 48mb flash 256mb ram. Both running IOS c2600-adventerprisek9-mz.124-15.T14.bin
2x 2950 Switches. Both running IOS c2950-i6k2l2q4-mz.121-22.EA8a.bin
1x 3550 Layer 3 Switch. IOS c3550-ipservicesk9-mz.122-55.SE10.bin
Accessories: 3x WIC-1T and 1x NM-4A/S Module

I have been studying for the CCNA for a few months now and looking at my lab setup I think that I need another router for a total of 3x routers.
Should I just get another 2651XM and max out the ram and flash or should I go for a 2811 with 512mb ram and 128mb flash with IOS 15.
I guess what I am asking is will only using 2651xm’s get me through my exam (Looking to take the 200-120) or should I be getting more experience with newer routers like the 2811 with IOS 15?
I have been playing around with IOU and gns3 but I want to get as much real world network hardware experience as possible.
Any tips and or suggestions would be greatly appreciated.