Exact same internals.
I don't buy the "design flaw" idea as I've never seen that cyl head CAUSE problems in itself on any other 5 cyl Volvo engine since its first year in the US (fall '92 as a '93 model).
The cause of your problems was simply too much boost and unless you turn it down to a reasonable level, you WILL do it all over again.
The safest way to "mod" your car is to run near stock boost (if not stock), get a "perf" ECU (like from IPD or similar), larger low restriction exhaust.