Unless you need 40 gig uplinks or are building a spine and leaf setup with the QFX products, I'd steer clear of the 4300's for now. Their code train has quite a few bugs that Juniper is sitll working out. 3300's and 4200's are pretty solid though, 10 gig uplink limit for these though. The 3300 will require an RPS (redundant power supply) system for power redundancy if you need that, as it only has one built in psu.
pbishop said it. that 4300??? Whenit is mature, I think it will turn out to be beast, When it is mature! So the next thing you want to do is to think about what you want to achieve, how you want want to build the network. Then verify that the features you are looking for are available and see which ones require a licnese for the specific platform.Check if version supports the feature and how said feature is implemented. Maybe more time consuming but brings less heartaches. EX 4200s are solid for everything! Don't know much about the 3300s, but mst be good for access and ToR.
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