Old school combat oriented scenario with strong foes but a weak introduction that could leave your players frustrated and considering "degenerate" solutions. The players have to go with the flow to get the scenario moving in the direction intended. Though the weak setup and player motivation issues are fixable with extra GM prep there remain a number of issues with the scenario.
There are three sub missions two of which have 2 encounters and one of which has 1 encounter. This makes 5 core encounters which at this power level - where encounters take longer - is too many. Three of these encounters can fill a 4 hour slot. There is also a further optional encounter which will rarely if ever be played except in home games.
Role play opportunities are only really partially limited to one of the encounters as written so make the most of what you are given.
I have run this twice and both times have run out of time with the number of encounters in anearly five hour session. If I run it again I think will have to cut both pre-encounters to make it fit in a 4 hour slot. This would also reduce the large prep overhead of this module.
The encounters are however strong and memorable being mostly iconic and potentially deadly with most of them having some sort of "nova" capability that could kill a PC if they are unlucky.
I found that compared to other scenarios, even tier 5-9 scenarios, I had a long list of things to look up before I could run this scenario. Partly this is the price of running high level scenarios, partly the choice of creatures and powers and partly the number of combat encounters.
As mentioned in other reviews a combat character light party or just an unlucky party will struggle with this so be prepared.
This is the scenario to roll out when you have a couple of slots to run it in, you want a hard fight with iconic monsters and you are comfortable with the possibility of PC death - though you need a strong GM who will spend the above average prep time and comfortably handle the issues to do it justice.