if I want fast speed I would use 2 talktak 80/20 lines giving me 160/40. for only a few quid more. I do have to supply my own load balance router though.
all you get with a router that does "Load Balancing" , is exactly that, one load giving you 80/20 and the other load giving you 80/20, you don't get bonding of the two 80/20 lines to give you 160/40, for that you need something a little more sophisticated than a cheap router that just does Load Balancing or Failover ( even the more expensive Draytek Vigor routers don't do proper Bonding of 2 lines ( and they never have done contrary to popular belief in these forums )