Probably about as strong as a bent/curved bar although the probability of them snapping goes up since curved bars will usually bend at the curve while these may snap at the weld.
But... any where there is a welded joint is an area prone to failure because the surrounding material-- HAZ, Heat Affected Zone is always weaker.
Welding up a set of bars like that would cost too much in labor for mass production, be way quicker to bend.
The inside Hand Grips of the Y sure looks like an easy way to open up yer face iffin' ya face plant in to the bars.
I think you said you were capping the tubing though.
Have a Good T Day, off to the Skate park for us and then Football, Food and a Nap- for me!!