we use the BT Digital Baby Monitor Plus, we did use to have a tony one but, currently we live with my parents and they live in a large old cottage, so in the summer the rooms would get sooo hot like 30degrees and the temp alarm would aways go off and you couldnt turn it off. Also the range wasnt great, and wouldnt reach all the rooms.
We went for the BT digital, as it has a temp range and you can set the ranges, and turn the alarm off if needed. Also it has 5 lullabys, and these are really handy as Leah drifts off to sleep during the night listening to them.
Hope this helped