First of all, this is a retrospective review by LGR:
https://www.youtube.com/watch?v=ZjS6rLKnU0c I recommend giving it a watch.
If you are just looking for gameplay like UT then no, don't bother. I personally have never enjoyed Deathmatch in Unreal (others will argue that Unreal Deathmatch is superior to UT).
For all intents and purposes, Unreal Multiplayer was a beta for UT.
Unreal is a great SP game but it dose show it's age (much like UT). On your first play through of unreal it will take you a long time, particularly on a select few levels, you will get lost, you will have no idea what is going on or what you are supposed to do on your first play through (any one reading this who has played unreal will know the levels I'm talking about). However if you have the mind to explore and work through it then overall you will absolutely enjoy it.
If you don't like reading then Unreal isn't really for you, in saying that, a large chunk of the community weren't able to read English the first time they played and still loved it.
Parts of the SP campaign have stuck in my mind from the very first play through and if I could I would go back and experience them for the first time again.
GreatEmerald dose a lets play on his YouTube channel if you want to get the feel for it's gameplay. (But don't watch too much, spoilers etc.).
As far as COOP goes, yes you can play with friends. However, the vanilla COOP isn't great. I personally have not played around with the various mods people have made to improve upon COOP, someone else here will be able to tell you about the different versions.
Operation NaPali isn't much like Unreal at all, it was built for more powerful computers by people who knew how to really push the engine. Do not expect Level geometry like ONP in Unreal. ONP was also built to be as much a comedy as a FPS (IMHO), Unreal takes itself much more seriously. ONP also contains ALOT of custom code and content (Cut scenes, followers, modified monsters etc.).
Will you have fun? In my heavily biased opinion yes! (I have been playing it for 17 years or so...)
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If you are into mapping at all then Unreal with the 227 patch is far superior to UT. The 227 patch introduces a whole bunch of new content for map makers and modernises the engine a bunch. Personally, while building a map for UT I will build the first 80% or so in Unreal227 then finish it in UT. I cannot recommend the 227 engine enough for mapping.
You can also play UT in unreal (sans the actual Tournament) by using Dots port of Botpack (also a staple for building UT maps in 227).
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Sorry about my vague rambles...
What you should take away from this is if you are unsure then wait until Unreal is discounted on GOG or Steam to purchase it. Otherwise if you have the money to burn then just go for it!
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