Beware, as far as I recall the 30E doesn't feature hardware acceleration of IPsec traffic - there's no NP or NPlite ASIC included. If that is the case the tiny CPU could have a difficult time with higher WAN bandwidth.
The hardware features of the 30E can be found somewhere on the forums.
The Product Matrix lists 75 Mbps for IPsec throughput, probably without any concurrent UTM features. This might be enough for your purposes.
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