If the VPN is important to you need to stretch your budget.
A refurbished AC1900P can be had on Amazon for US$89 and with its 1400 Mhz processor it will give you download speeds of 50 - 60 Mbps when using a VPN client. For a few dollars less you might find a standard AC68/AC1900 but with a slower processor your VPN speeds will be less.
While you might find someone to sell you an old N66 in your price range the best a VPN client on this router would do on this router is downloads of 10 - 15 Mbps as its processor is only 600Mhz. In addition the N66 is no longer supported by Merlin so if you would need to flash Johns fork which he keeps up to date with patches.
I don't believe the model you inquired about is currently supported by Merlin.
Looking for an ASUS router with OpenVPN capability (preferably Merlin support as well). Found the RT-N12HP for a reasonable price, but I'm not sure if it supports an OpenVPN client.
Budget: under $60
If you're willing to stretch your budget you can step up to an RT-AC87U. I see one on eBay for $63, or several and several at Amazon for $90-$100. It would doubtless be worth the extra money.
RMerlin had this to say about OpenVPN on the RT-AC87U, "As I expected, this router is a beast for OpenVPN. Performance should be close to that with the GT-AC5300 (Asus's OpenVPN isn't entirely as optimized as my implementation, but it shouldn't be far behind). So basically, expect around 200 Mbps of throughput." post
Sky
You meant say RT-AC86U....[emoji6]. The RT-AC87U is a completely different toy.
An RT-AC87U won't be breaking any OpenVPN speed records, it has no hardware accelerated AES. Same CPU as the RT-AC66U_B1, which would be a better purchase, as it gets more support from Asus.
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