We have spotlights on our barn and house which are pointed to the arena and they work just great.
I do vote for paying someone with the equipment, training and insurance to put up and change this stuff despite being one half of a strictly DYI couple.
But whatever you decide buy the bulbs from a reputable dealer, test them all before the installer arrives (or starts up the ladder) and have extras on hand.
Jeesh, I may test them in the doggone store next time just for laughs.
Oh, and look out for compatibility issues between the newer energy efficient bulbs which are not compatible with the older model spot light fixtures.
Good luck. Its fun to ride at night.