4.0 Piston Interchange 87-95 with 96-2006

[MoFo]

I did search; Maybe the answer is so obvious I should hav known. If this is the case, please accept my humble apology.

I am shopping for a set of pistons. I see there are 2 different types available from the manufacturers:
1987 to 1995
1996 to 2006

The only difference I can see in these is the early pistons use SAE rings of 5/64", 5/64" and 3/16".
The later pistons use metric rings of 1.5mm, 1.5mm and 4.0mm.

Are thes completly interchangable, as long as I use the right size ring for the piston ring land?
I have a line on an inexpensive set of the later pistons and want to put them in a stroked RENIX engine.

[6TIME]

That's the only difference. The metric rings are slightly thinner and they claim that it reduces cylinder wall friction....how much and is it worth it? Dunno..