LED's is the way to go - you won't find anything with a filament that will stack up. Not even close.
And stay away from the LED replacements you see sold in auto parts stores...
They're not only poor quality, they're really not all that bright.
Custom Dynamics or BAL's aren't cheap, but this is one of those times when you really do get what you pay for.
Their lifetime warranty doesn't hurt either - and they DO stand behind it.

I can tell you this about mine - I used to get tailgated before my upgrade, but since then, not so much.
People WILL back off.
My LED running lights are now brighter than the stock brake lights were, and when you do hit the brakes, it's like "holy ****" to anyone behind you.

This is an attempt to take a picture with the lights on, and it's not easy to get a good shot.
This picture was taken with the bike backed out into my driveway on a bright sunny day.
They're so bright they just take out the rest of the picture - it's like looking into a laser pointer.

 

I would stick with a good LRD option.

I've ridden HDs since the '70s. I have never been hit, and the OEM brake lights have worked just fine.

But these days, there are new and many distractions for drivers.... cell phones just one example....

That is why in 2012, on my Limited, I opted for a really good LED tail light (BAL-1). I liked it so much, I put one on my '03 Heritage.

Get the best LED set-up for your tail light you can afford..... you may never know how many times it saves your butt....!

Good luck