I was reading the reviews of BG and it´s family games, and IWD gor pretty "varying" reviews. Is it nearly as good as BG series? What are the biggest differences? How about, is there enough challenge <=> how long the game lasts etc etc..?

Its just so impossible to trust online reviews.. you never know who the reviewer actually is.

I enjoyed IWD myself, it is a little different than BG in that you create your own party and their are no NPC's to join. It also keeps areas locked until you solve a quest to get the area on your map so you can't go wandering around the wilderness like BG. The dungeon's are usually far larger and more challenging than anything in BG at least I found that they were with the exception of BG expansions. I would give it a 8 on a scale of 1 to 10. It is defiantly worth playing.

However, despite excellent graphics and good gametime battles, the plot of the whole thing is fairly linear, and it doesn't have hardly any side quests outside of those necessary inside an individual dungeon. I enjoyed the game however, and it provided me with a nice opportunity to create a party i enjoyed playing with. It was IWD incidentally that turned me on to the surprising capablites of bards.

the game is a nice return to the old gold box games style of dungeon crawl, don't expect much more than a dungeon crawl out of it though (although it is a really great one), BG is an epic, this is a hack-fest, as has been said before, don't expect nearly the amountof characterization as BG1 or 2, but do expect alot of fun.

<font color = mediumspringgreen>NiceWorg,

The official word, I think, is something like 30 hours of gameplay for IWD and another 20 for HoW. I think I saw a post from someone who actually did it over one weekend, with very little sleep. However, I am about halfway through IWD with my first party, almost halfway through with the second (know what I am doing this time) and have easily spent over 80 hours on the game! (I know, I am a slowpoke!)

You cannot even come close to fitting all of the varied classes into one party; so even without the HoW-added features, like Heart of Fury mode, this game has excellent replay value.

Party On!
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I too am a slowpoke when going through the game, but I have no idea how many hours it took me to complete it. Probably over 100 for sure.
Good Dungeon crawl, that gave a breath of air to the Bioware/Interplay, et.al. games. I enjoyed BG1. I enjoyed IWD. I'm enjoying BG2. They are all good and worth playing.