It depends on exactly what you want to accomplish with your VPN. For instance, if the issue is due to downloading items of a somewhat illegal nature, i.e. peer to peer stuff, some VPN services don't allow that anyway, so it's best to do a little research on the VPNs you might want to try.
Personally, we use Private Internet Access, and have had no issues with them. Slowdowns also depend on your location, and the location of the VPN's server you're connecting to. For instance, we're located near Vancouver, and strange as it may seem, our connection to servers in California tends to be better than connecting to servers in Seattle. When I was looking for the same thing, someone else, that lives, IIRC, in Halifax, had used PIA, and found that their connection suffered significant slowdowns, so they switched to another VPN, and it was apparently much better.
Also, be sure to check each VPN out so far as allowed bandwidth, and whether or not they keep any logs of their customers' activities.
As for Tunnel Bear, I don't recall specifics, but I do recall checking them out, and I THINK they had a rather small bandwidth limit.
In doing some research, you'll also notice there's often a significant price difference between VPNs too.
Most of them have OS-specific apps to install, and some of them allow a 2 or 3 day trial, or you can subscribe for a week, just to try them out. They all generally allow several simultaneous connections, but some allow more than others.
I can't speak for the others, but PIA is actually pretty damn good - they have A LOT of servers worldwide, they're very reasonably priced, they don't log activities, they allow peer to peer, their app is VERY easy to config & run, and they allow several simultaneous connections. Some of the supposedly good ones include Nord, Pure, IP Vanish, but I'd suggest you do some research.... maybe Google "best vpn", or "top 10 vpn".
You don't really need to put that other router in the equation.... just install the app on the devices in question, and connect that way. You can connect & disconnect at will, or config the app to start at bootup, and auto-connect. If it's a matter of wanting to connect more devices simultaneously than their allowed number, or just wanting to make sure that anybody using your internet connection is using your VPN, THEN you might want to install a VPN config on your router.
Hope that helps :thumb: .... any more questions, just fire away. :biggrin: