Need advice on outdoor lighting dilemma. What we have is custom-made recessed low voltage lights installed in a wall. The bi-pins are making us crazy because the MR16 bulbs keep loosening and falling out of their sockets (remember they are mounted vertically).

After some research, I have narrowed the replacement possibilities to two:

1) Stick with the low voltage and replace bi-pin sockets with GU7 twist & lock types and get the right MR16 bulbs for the new sockets. My concern with this option is the heat build-up that might occur; the bulb sits inside a tube which is closed with a lens cover.

2) Switch over to line voltage and give up on the 12 v stuff so the bulbs can screw in instead of plug in. Also the heat build-up becomes less of a concern, or does it?

Or is there another option I am missing? Or any other concerns with the two options above that I should know about?

Thank you.