Service Grade parts versus Professional Grade parts

[OldSub]

I've been looking at suspension parts to rebuild the IFS I'm putting in my '54 GMC 1-ton.  The IFS is from a '72 Chevy C20 and I was checking prices at http://www.rockauto.com/catalog/catalogframe.php.

For the ball joints and shafts there are at least two grades of parts listed and some of them are less than half the price of others.

The cheap parts are listed as Private Label or Service Grade and the more expensive are Professional Grade or Problem Solver.

I'm inclined to buy the Professional Grade parts but don't want to be stupid.  Do those labels still mean anything?  Or am I getting a cheapest bidder Chinese made part either way?

Anyone have a good handle on this?

[unklian]

I put new tie rod ends on my car a couple years ago,
3 made in Usa, one made in Mexico.

Of course, now the Mexican one is worn out, the others are fine.

Steering parts from China ?
I would rather not.

At least ask where this stuff is made.

[enjenjo]

The professional grade parts are better quality. Even if made in China, they can make better parts that are just fine. Most parts stores now carry two lines, one that competes on price, the other on quality.

[OldSub]

The professional grade parts are better quality.

Then those are the ones I'll buy.

Thanks!