Welcome to the CAC!!!
I've driven both LT1 (also an automatic) and LT4 equipped Corvettes, and I think the real issue with this is that it's harder to objectively compare the automatic vs. the manual than it is an LT1 vs. an LT4. I'm biased, because imo, the manual is always better. But that's really just a matter of opinion. I prefer to do the shifting myself, because I feel I get better power and performance that way.
Also, keep in mind that the LT4 is rated 30 horses higher than the LT1. Many believe the LT4 to have been under-rated in terms of horsepower by Chevy at the time it was introduced, so as not to have a base model engine in the last model year C4 have more HP than the next model year's base C5. The LS1 was rated at 345 horsepower, I believe, for the 1997 model year. In other words, a marketing decision. You can google horsepower for the LT4 and see a lot of info (dyno's) to support this position.
With that in mind, I would even recommend a manual LT1 vs. an automatic LT1. So, if all other considerations were equal between an LT1 automatic and an LT4, I would obviously recommend the LT4. I am baised, but I think it's based on experience of ownership!
Trust me, you will be pleased with the LT4's perforanmance!
If you're worried about this particular LT4's mileage, then you could probably hold off and find another LT4 with less miles, at a reasonable price. It's a buyer's market right now. There's a red LT4 coupe advertised around here (SF bay area) on craigslist for $11.5K, and it's been available for a while. I'd be willing to bet the owner would take less than the asking price.
An LT4 certainly can deliver the goods while painted red... it doesn't have to be a Collector Edition, although imo, SILVER is the best color for a Corvette!
Good luck, and don't forget to
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