Failover/increase speed

We have broadband over BT landline.
But it is slow (best speed around 1.5mbps) and not very reliable.
(everyone around here is similar, but FTTC is not expected until late 2017).

We have a small network (4 x PCs), but we need to have faster and more reliable broadband.

We have a Draytek Vigor 2800 router.
What options do I have for adding mobile broadband to aggregate the speed/improve reliability ?
I have a 4G EE phone which gets a broadband speed of around 4.5 mbps (we are just on the edge of the EE map).

I see there is another model of the router which can also have a Sim card. Is that the way to do this ?
Or can I connect a mobile router as well ?

I'm a little concerned about going mobile only because sometimes my phone drops back to 3G.

Presume the Vigor 2860 load balancing router, the sales stuff talks of load balancing but nothing to confirm it will work across the ADSL and a 3G/4G device. Certainly across two ADSL lines is possible.

Might be better to go for something like Quad WAN load balancer and then just concentrate on getting the various methods available as Ethernet e.g. use something like this Huawei router to host the SIM card.

Another option is something like the Asus RT-N66U which others a load balance or fail-over mode from the Ethernet WAN with the USB 3g/4G interface (i.e. just get a compatible USB dongle). The Asus router with same mode (I believe) and a built in ADSL modem is the DSL-N66U

PM Me a postcode and I'll see what upgrades are planned in your local area.

In reply to a post by MrSaffron:

Presume the Vigor 2860 load balancing router, the sales stuff talks of load balancing but nothing to confirm it will work across the ADSL and a 3G/4G device. Certainly across two ADSL lines is possible.

Might be better to go for something like Quad WAN load balancer and then just concentrate on getting the various methods available as Ethernet e.g. use something like this Huawei router to host the SIM card.

Another option is something like the Asus RT-N66U which others a load balance or fail-over mode from the Ethernet WAN with the USB 3g/4G interface (i.e. just get a compatible USB dongle). The Asus router with same mode (I believe) and a built in ADSL modem is the DSL-N66U

I'd recommend the quad wan load balancer I have one of those and they work brilliantly and round robin all the time so I get all the speed I can push

Thanks Andrew,

What is the model of the Huawei router ? (that link was faulty).

With the load balancer, is it possible to set it up so that light loads (such as regularly picking up emails) normally go via landline and mobile is only used for heavier loads ?
(Just to save using up the mobile data allowance).

Huawei b593