Not been on here for a while since you very helpful people helped me out last time.
I could not find a cat over here in the UK for my 99 4.3 so i had a straight pipe put in.
Seems a bit quicker, but it might just be me booting it more because it sounds better.
Going to fit a cold air kit next, just need a filter.
British Blazer

 

removing the cat, adding a cold air kit or an aftermarket air filter is going to do absolutely nothing in the way of usable horsepower. nobody will ever show you a dyno sheet that says otherwise. you may a get 5hp-7hp gain from both combined but it will be at the top end of the power curve and unless you race the truck, you'll never see that gain. realistically speaking, how often is that motor run above 5000 rpm? if it's an issue for you, once you remove the cat you will also set the SES light due to your rear o2 sensor readings. the cold air kit will let you hear the motor sucking air through it while you on the gas and the test pipe will make the truck sound louder, both of which may give the appearance of more power but unless you are heavily modded dont expect much from these changes.