Well we also went from a 270 laser with the 502 mag and it was an awesome boat for lake erie boating, once we moved up to the Vyper with 500 HP's what a difference, the ride and power is awesome, we see 78 GPS in a nice chop and it can take the rollers on lake erie with out taking a beating at all, the avenger does have a bit nicer ride in the real ruff stuff but overall not much difference between the two in ride on a regulat basis, allthough the Vyper is a bit faster i believe with equal power. Either way both boats are great and you wont be dissapointed at all with either one, just make sure you get it with the power you want. Gotta have the blue motors, just my opinion.

I was wrong
 

You are correct the Avenger is a far different ride than the Viper. The Avenger is better in the rough water , has less bow rise and rides flat when up. Not sure why I said that.
However with identical power the Viper will be faster.
If speed is what you want find an Avenger with the 575sci's
Stock you are in the mid 80'S and with only a pully change you can get over 90

34 vs. 38
 

Have spent time in the 34' and own a 2002 38'. Both ride well but I run my boat at LOTO and I pat myself on the back every boat ride that I went with the 38'.

Cabin is much larger, a little more headroom even. Cockpit is one of the most sizable I have seen, can have three to four behind the bolsters without stepping on the people's feet sitting on the bench. Have had 12 in the cockpit, although it is not very comfortable.

Head is easy to use, a lot of room.

I have 500EFI's with 130 hours, XR drives with IMCO shorties, and Hydromotive P5X 30" 5 blades that have been labbed. Boat with run 81-82 on fumes and 75 all day with 6 people and beer.

Rough water? Don't even get me started on LOTO, it takes all that it can give.

Lastly, I am debating putting mine up for sale so if interested, let me know.

Mine with 496HO's has a top end best speed on GPS of 81 on the ocean and will regularly hit 78-79 in any condition. Mine is 2002 with every single option that could add weight. HP500's should push to 83-85 mph and 525's would hit upper 80's.

Viper Speed
 

Never heard of a Viper in the upper 80s yet. Any out there?

We have a 38 Avenger in the lower Green Bay area with twin 650 H.P. custom motors that just touches 90mph. I would think a 34 Vyper would need at least 575's to get close too that speed?

Well I am doing my motor upgrade this winter to the 650 Hp range, 500 HP's with AFR 315's and new crane 731 cams with new MSD ignition and distributers, I am told we should see 625-650 Hp with the set-up, allready installed hydromotive nose cones on the drives. Hopefully see 85-87 MPH with the new set up as I am allready running 78-80 in current configuration. Would love to see a Vyper hit the 90 mph zone.