e300 vs mx240 for border router ?

[leslie at craigslist.org (Leslie)]

Hey nanog-izens

So for routers that are touching our transit and (hopefully soon) future 
peering, we're looking at both the force10 e300's and juniper mx240's. 
The e300's are cheap but I have heard some rumors/talk of falling over 
when it has to deal with large numbers of prefixes and routes?  The 
mx240's are nice but the cost difference is enormous.  Does anyone have 
experience with e300's running into issues with large routing tables? 
Are there any tricks/tips that work around any issues (if they exist?)

Thanks in advance

Leslie