I always find when I'm making burgers using beef mince that if I use the best quality mince, and therefore the most expensive, it never has as much beef flavour as I would like. I think its probably because top quality beef mince is very lean and when it comes to meat, the flavour is in the fat. Its a balance between decent meat and flavour so I compromise and use the second best mince available at the butcher, usually topside mince. Its still leaner than really cheap mince but has just enough fat to give the meat a great beefy flavour.
You can make the mince mixture for these yummy little morsels well in advance if you like, and then its just a matter of cooking the burgers so they make a really quick meal. The shaped patties would store well, covered, in the fridge for a couple of days before cooking.