Without hesitation, I heartily endorse the Markham toothbar
{HERE}.
Allen Markham builds a great product, sells it for a reasonable price, and provides excellent support with prompt shipping. Believe me, I've looked around at a number of manufacturers. All seem to be fine products, but either the cost is too high, shipping is too high, or the mfr only sells through tractor/ag dealer, which bumps the price yet again. You can find some other mfrs that I listed at a previous post on toothbars
{HERE}
I have the Markham on my light materials bucket (LMB) and 4n1. I can't believe the change for the better in the LMB. The bar has strengthened the floor and sidewalls, and it's a real digger now. As has been said, the bar is removable with two bolts. However, I find that I am learning to back-drag with the bottom of the LMB so I don't feel the need to remove the toothbar to do that task.
Me thinks that a lot of PT owners and TBNers endorse the Markham. Just do a search of posts for 'Markham' over the last 6 months or so, and you'll be convinced.
Have a Happy New Year, and great tractoring in 2006