The lack of power came with some time, stronger and stronger, so it is as You say, not a sudden effect, i must said not right in the topic.
for replacement kat, i am from Lithuania, hope You know where it is:), so getting one prom pro-lex would be difficult, however interesting.
as for the decoration on the exhaust, yes i mean exhaust tip. I have no pictures here, but i can explain. The chrome tip, that was on the exhaust pipe had 4 cm smaller hole than the stock pipe, i mean 2 cm from one side, so around gets 4 cm. I noticed that car got sluggish, so after 2 months i took it of. I think someone said it also could be the reason why it choked, because the exhaust system is very sensitive?